Document and Entity Information - USD ($)	12 Months Ended
Document and Entity Information - USD ($)	Dec. 29, 2018	Jan. 31, 2019	Jun. 29, 2018	Dec. 30, 2017
Document and Entity Information [Abstract]
Common Stock, Shares, Outstanding	27,788,272			27,945,144
Entity Registrant Name	IROBOT CORP
Entity Central Index Key	0001159167
Document Type	10-K
Document Period End Date	Dec. 29, 2018
Amendment Flag	false
Document Fiscal Year Focus	2018
Document Fiscal Period Focus	FY
Current Fiscal Year End Date	--12-29
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Public Float			$ 2,000,000,000
Entity Common Stock, Shares Outstanding		27,796,614

Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 29, 2018	Dec. 30, 2017
Current assets:
Cash and cash equivalents	$ 130,373	$ 128,635
Short term investments	31,605	37,225
Accounts receivable, net	162,166	142,829
Inventory	164,633	106,932
Other current assets	25,660	19,105
Total current assets	514,437	434,726
Property and equipment, net	57,026	44,579
Deferred tax assets	36,979	31,531
Goodwill	118,896	121,440
Intangible assets, net	24,273	44,712
Other assets	15,350	14,534
Total assets	766,961	691,522
Current liabilities:
Accounts payable	136,742	116,316
Accrued expenses	71,259	73,647
Deferred revenue and customer advances	5,756	7,761
Total current liabilities	213,757	197,724
Deferred tax liabilities	4,005	9,539
Other long-term liabilities	13,877	13,932
Total long-term liabilities	17,882	23,471
Total liabilities	231,639	221,195
Commitments and contingencies (Note 14)
Preferred stock, 5,000 shares authorized and none outstanding	0	0
Common stock, $0.01 par value, 100,000 shares authorized; 27,788 and 27,945 shares issued and outstanding, respectively	278	279
Additional paid-in capital	172,771	190,067
Retained earnings	367,021	277,989
Accumulated other comprehensive (loss) income	(4,748)	1,992
Total stockholders’ equity	535,322	470,327
Total liabilities and stockholders’ equity	$ 766,961	$ 691,522

Consolidated Balance Sheets (Parenthetical) - $ / shares	Dec. 29, 2018	Dec. 30, 2017
Statement of Financial Position [Abstract]
Preferred stock, shares authorized	5,000,000	5,000,000
Preferred stock, shares outstanding	0	0
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized	100,000,000	100,000,000
Common stock, shares issued	27,788,272	27,945,144
Common stock, shares outstanding	27,788,272	27,945,144

Consolidated Statements of Income - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 29, 2018	Dec. 30, 2017	Dec. 31, 2016
Revenue	$ 1,092,584	$ 883,911	$ 660,604
Cost of product revenue	518,612	438,114	337,832
Amortization of acquired intangible assets	18,544	12,638	3,457
Total cost of revenue	537,156	450,752	341,289
Gross profit	555,428	433,159	319,315
Operating expenses:
Research and development	140,629	113,149	79,805
Selling and marketing	210,411	162,110	115,125
General and administrative	97,501	84,771	66,828
Amortization of acquired intangible assets	1,065	439	0
Total operating expenses	449,606	360,469	261,758
Operating income	105,822	72,690	57,557
Other income, net	2,800	3,676	3,804
Income before income taxes	108,622	76,366	61,361
Income tax expense	20,630	25,402	19,422
Net income	$ 87,992	$ 50,964	$ 41,939
Net income per share:
Basic	$ 3.18	$ 1.85	$ 1.51
Diluted	$ 3.07	$ 1.77	$ 1.48
Number of shares used in per share calculations:
Basic	27,692	27,611	27,698
Diluted	28,640	28,753	28,292

Consolidated Statement of Comprehensive Income - USD ($) $ in Thousands	12 Months Ended
	Dec. 29, 2018	Dec. 30, 2017	Dec. 31, 2016
Statement of Comprehensive Income [Abstract]
Net income	$ 87,992	$ 50,964	$ 41,939
Other comprehensive income (loss):
Net foreign currency translation adjustments, net of tax	(5,896)	1,994	0
Net unrealized (losses) gains on cash flow hedges, net of tax	(327)	490	0
Net gains on cash flow hedge reclassified into earnings, net of tax	(499)	(295)	0
Net unrealized (losses) gains on marketable securities, net of tax	(18)	(46)	85
Total comprehensive income	$ 81,252	$ 53,107	$ 42,024

- Definition

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

+ References + Details

Consolidated Statements of Stockholders' Equity - USD ($)	Total	Common Stock	Additional Paid-in Capital	Retained Earnings (Accumulated Deficit)	Accumulated Other Comprehensive Income (Loss)
Beginning balance, shares at Jan. 02, 2016		29,091,806
Beginning balance at Jan. 02, 2016	$ 417,411,000	$ 291,000	$ 232,345,000	$ 185,011,000	$ (236,000)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock for exercise of stock options (in shares)	456,498	456,498
Issuance of common stock under employee stock plans	$ 9,344,000	$ 4,000	9,340,000
Conversion of deferred compensation	6,721
Vesting of restricted stock units (in shares)		363,643
Vesting of restricted stock units	$ 0	$ 4,000	(4,000)
Tax benefit of excess stock-based compensation deduction	2,421,000		2,421,000
Stock-based compensation	15,995,000		15,995,000
Stock withheld to cover tax withholdings requirements upon vesting of restricted stock units (in shares)		(39,676)
Stock withheld to cover tax withholdings requirements upon restricted stock vesting	(1,300,000)		(1,300,000)
Other comprehensive income (loss)	85,000				85,000
Directors' deferred compensation	$ 82,000		82,000
Stock repurchases (in shares)	(2,641,122)
Stock repurchases	$ (97,021,000)	$ (27,000)	(96,994,000)
Net income	41,939,000			41,939,000
Ending balance, shares at Dec. 31, 2016		27,237,870
Ending balance at Dec. 31, 2016	$ 388,956,000	$ 272,000	161,885,000	226,950,000	(151,000)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock for exercise of stock options (in shares)	367,267	367,267
Issuance of common stock under employee stock plans	$ 10,573,000	$ 4,000	10,569,000
Conversion of deferred compensation	14,901
Vesting of restricted stock units (in shares)		376,335
Vesting of restricted stock units	$ 0	$ 4,000	(4,000)
Stock-based compensation	19,751,000		19,751,000
Stock withheld to cover tax withholdings requirements upon vesting of restricted stock units (in shares)		(51,229)
Stock withheld to cover tax withholdings requirements upon restricted stock vesting	(2,983,000)	$ (1,000)	(2,982,000)
Other comprehensive income (loss)	2,143,000				2,143,000
Directors' deferred compensation	65,000		65,000
Net income	$ 50,964,000			50,964,000
Ending balance, shares at Dec. 30, 2017	27,945,144	27,945,144
Ending balance at Dec. 30, 2017	$ 470,327,000	$ 279,000	190,067,000	277,989,000	1,992,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Cumulative effect of a change in accounting principle	$ 858,000		783,000	75,000
Issuance of common stock for exercise of stock options (in shares)	239,830	284,731
Issuance of common stock under employee stock plans	$ 10,366,000	$ 3,000	10,363,000
Vesting of restricted stock units (in shares)		408,075
Vesting of restricted stock units	0	$ 4,000	(4,000)
Stock-based compensation	25,804,000		25,804,000
Stock withheld to cover tax withholdings requirements upon vesting of restricted stock units (in shares)		50,884
Stock withheld to cover tax withholdings requirements upon restricted stock vesting	3,532,000	$ 0	3,532,000
Other comprehensive income (loss)	(6,740,000)				(6,740,000)
Directors' deferred compensation	$ 65,000		65,000
Stock repurchases (in shares)	(798,794)
Stock repurchases	$ (50,000,000)	$ (8,000)	(49,992,000)
Net income	$ 87,992,000			87,992,000
Ending balance, shares at Dec. 29, 2018	27,788,272	27,788,272
Ending balance at Dec. 29, 2018	$ 535,322,000	$ 278,000	$ 172,771,000	367,021,000	$ (4,748,000)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Cumulative effect of a change in accounting principle	$ 1,040,000			$ 1,040,000

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 29, 2018	Dec. 30, 2017	Dec. 31, 2016
Cash flows from operating activities:
Net income	$ 87,992	$ 50,964	$ 41,939
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	36,574	25,499	13,606
Gain on business acquisition	0	(2,243)	0
Stock-based compensation	25,804	19,751	15,995
Deferred income taxes, net	(10,848)	(999)	3,557
Tax benefit of excess stock-based compensation deductions	0	0	(2,971)
Deferred rent	1,374	0	0
Other	463	864	(2,361)
Changes in operating assets and liabilities — (use) source
Accounts receivable	(23,920)	(53,251)	25,682
Inventory	(58,546)	(1,470)	(981)
Other assets	(8,533)	(10,562)	3,187
Accounts payable	22,470	17,457	6,502
Accrued expenses	(3,618)	23,447	10,181
Deferred revenue and customer advances	2,392	2,149	2,996
Long-term liabilities	81	4,709	(908)
Net cash provided by operating activities	71,685	76,315	116,424
Cash flows from investing activities:
Additions of property and equipment	(32,422)	(23,371)	(10,817)
Change in other assets	(2,363)	(1,542)	(2,093)
Proceeds from sale of equity investments	856	1,267	634
Proceeds from sale of business unit	0	0	23,520
Cash paid for business acquisitions, net of cash acquired	0	(148,765)	0
Purchases of investments	(6,438)	(10,578)	(16,554)
Sales and maturities of investments	14,000	13,066	9,500
Net cash (used in) provided by investing activities	(26,367)	(169,923)	4,190
Cash flows from financing activities:
Proceeds from employee stock plans	10,366	10,573	9,344
Income tax withholding payment associated with restricted stock vesting	(3,532)	(2,983)	(1,300)
Stock repurchases	(50,000)	0	(97,021)
Tax benefit of excess stock-based compensation deductions	0	0	2,971
Net cash (used in) provided by financing activities	(43,166)	7,590	(86,006)
Effect of exchange rate changes on cash and cash equivalents	(414)	130	0
Net increase (decrease) in cash and cash equivalents	1,738	(85,888)	34,608
Cash and cash equivalents, at beginning of period	128,635	214,523	179,915
Cash and cash equivalents, at end of period	130,373	128,635	214,523
Supplemental disclosure of cash flow information
Cash paid for income taxes	39,517	25,879	14,061
Additions of property and equipment included in accounts payable	$ 2,795	$ 5,001	$ 1,550

Summary of Significant Accounting Policies

12 Months Ended

Dec. 29, 2018

Accounting Policies [Abstract]

Summary of Significant Accounting Policies



2.	Summary of Significant Accounting Policies

Basis of Presentation and Foreign Currency Translation

The accompanying consolidated financial statements include those of iRobot and its subsidiaries, after elimination of all intercompany balances and transactions. iRobot has prepared the accompanying consolidated financial statements in conformity with accounting principles generally accepted in the United States of America ("GAAP"). In addition, certain prior year amounts have been reclassified to conform to the current year presentation.

For the Company's subsidiaries that transact in a functional currency other than the U.S. dollar, assets and liabilities are translated into U.S. dollars at period-end foreign exchange rates. Revenues and expenses are translated into U.S. dollars at the average foreign exchange rates for the period. Translation adjustments are excluded from the determination of net income and are recorded in accumulated other comprehensive income (loss), a separate component of stockholders' equity.

Use of Estimates

The preparation of these financial statements in conformity with GAAP requires the Company to make estimates and assumptions that affect the reported amounts of assets and liabilities and revenue and expenses. These estimates and judgments, include but are not limited to, revenue recognition, including performance obligations, variable consideration and other obligations such as product returns and incentives; warranty costs; valuation of goodwill and acquired intangible assets; valuation of financial instruments; accounting for business combinations; evaluating loss contingencies; accounting for stock-based compensation including performance-based assessments; and accounting for income taxes and related valuation allowances. The Company bases these estimates and judgments on historical experience, market participant fair value considerations, projected future cash flows and various other factors that the Company believes are reasonable under the circumstances. Actual results may differ from the Company’s estimates.

Fiscal Year-End

The Company operates and reports using a 52-53 week fiscal year ending on the Saturday closest to December 31. Accordingly, the Company’s fiscal quarters end on the Saturday that falls closest to the last day of the third month of each quarter.

Business Combinations

The Company accounts for transactions that represent business combinations under the acquisition method of accounting. The Company allocates the total consideration paid for each acquisition to the assets it acquires and liabilities it assumes based on their fair values as of the date of acquisition, including identifiable intangible assets. The Company bases the fair value of identifiable intangible assets acquired in a business combination on valuations that use information and assumptions determined by management and which consider management’s best estimates of inputs and assumptions that a market participant would use. While the Company uses its best estimates and assumptions as part of the purchase price allocation process to accurately value assets acquired and liabilities assumed at the business combination date, its estimates and assumptions are inherently uncertain and subject to refinement. As a result, during the measurement period, which is generally one year from the acquisition date, any adjustment to the assets acquired and liabilities assumed is recorded against goodwill in the period in which the amount is determined. Any adjustment identified subsequent to the measurement period is included in operating results in the period in which the amount is determined.

Cash and Cash Equivalents

The Company considers all highly liquid investments with maturity of three months or less at the time of purchase to be cash and cash equivalents. The Company invests its excess cash primarily in money market funds or demand deposit accounts of major financial institutions. Accordingly, its cash and cash equivalents are subject to minimal credit and market risk. At December 29, 2018 and December 30, 2017, cash and cash equivalents totaled $130.4 million and $128.6 million, respectively. These cash and cash equivalents are carried at cost, which approximates fair value.

Short Term Investments

The Company’s investments are classified as available-for-sale and are recorded at fair value with any unrealized gain or loss recorded as an element of stockholders’ equity. The fair value of investments is determined based on quoted market prices at the reporting date for those instruments. As of December 29, 2018 and December 30, 2017, investments consisted of (in thousands):



	December 29, 2018				December 30, 2017
	Cost		Fair Market Value		Cost		Fair Market Value
Corporate and government bonds	$	30,035	$	29,605	$	37,767	$	37,225
Convertible note	2,000		2,000		—		—
Total short term investments	$	32,035	$	31,605	$	37,767	$	37,225

As of December 29, 2018, the Company’s investments had maturity dates ranging from March 2019 to March 2021. The Company invests primarily in investment grade securities and limits the amount of investment in any single issuer.

Accounts receivable allowances

Allowance for product returns: The Company records an allowance for product returns for the estimated amount of product that may be returned. The allowance is based on specific terms and conditions included in the customer agreements, historical returns experience and various other assumptions that the Company believes are reasonable.

Allowance for other credits and incentives: The Company records an allowance related to customer incentives such as discounts, promotions, price protection and other support programs. The allowance is based on specific programs, expected usage and historical experience.

Allowance for doubtful accounts: The Company records an allowance for doubtful accounts for the estimated amount of accounts receivable that may not be collected based on an assessment of the potential risk of loss associated with delinquent accounts. The allowance including the activity within the allowance was immaterial for fiscal years 2018, 2017 and 2016.

Activity related to accounts receivable allowances was as follows (in thousands):



	Fiscal Year Ended
	December 29, 2018			December 30, 2017			December 31, 2016
Allowance for product returns
Balance at beginning of period	$	42,693		$	27,673		$	25,992
Acquired balance	—			6,088			—
Provision	68,476			54,981			33,992
Deduction	(56,164		)	(43,831		)	(28,826		)
Other adjustments	(1,085		)	(2,218		)	(3,485		)
Balance at end of period	$	53,920		$	42,693		$	27,673

Allowance for other credits and incentives
Balance at beginning of period	$	61,359		$	23,658		$	23,005
Acquired balance	—			11,932			—
Adjustment related to adoption of ASC 606	1,192			—			—
Provision	198,371			110,605			47,419
Deduction	(161,672		)	(81,269		)	(46,610		)
Other adjustments	(1,513		)	(3,567		)	(156		)
Balance at end of period	$	97,737		$	61,359		$	23,658

Inventory

Inventory is stated at the lower of cost or net realizable value with cost being determined using the first-in, first-out ("FIFO") method. The Company maintains a reserve for inventory items to provide for an estimated amount of excess or obsolete inventory.

Warranty

The Company typically provides a one-year warranty (with the exception of European consumer products, which typically have a two-year warranty period) against defects in materials and workmanship and will either repair the goods, provide replacement products at no charge to the customer or refund amounts to the customer for defective products. The Company records estimated warranty costs, based on historical experience by product, at the time revenue is recognized. Actual results could differ from these estimates, which could cause increases or decreases to the warranty reserves in future periods.

Property and Equipment

Property and equipment are recorded at cost and consist primarily of computer equipment, leasehold improvements, business applications software, tooling and machinery. Depreciation is computed using the straight-line method over the estimated useful lives as follows:



	Estimated Useful Life
Computer and research equipment	2-5 years
Furniture	5
Machinery	2-5
Tooling	2-5
Business applications software	3-7
Leasehold improvements	Lesser of economic benefit period or term of lease

Expenditures for additions, renewals and betterments of property and equipment are capitalized. Expenditures for repairs and maintenance are charged to expense as incurred. As assets are retired or sold, the related cost and accumulated depreciation are removed from the accounts and any resulting gain or loss is recognized.

Goodwill and Other Long-Lived Assets

Goodwill represents the excess of the purchase price in a business combination over the fair value of the net tangible and intangible assets acquired. Goodwill is not amortized but rather is assessed for impairment at the reporting unit level (operating segment or one level below an operating segment) annually during its fourth quarter of each fiscal year or more frequently if the Company believes indicators of impairment exist. Goodwill impairment, if any, is determined by comparing the reporting unit's fair value to its carrying value. An impairment loss is recognized in an amount equal to the excess of the reporting unit's carrying value over its fair value, up to the amount of goodwill allocated to the reporting unit.

Other long-lived assets consist principally of completed technology, tradename, customer relationships, reacquired distribution rights and non-competition agreements. Reacquired distribution rights are amortized on an accelerated basis while all other intangible assets are amortized over their respective estimated useful lives on a straight-line basis, consistent with the pattern in which the economic benefits are being utilized.

The Company periodically evaluates the recoverability of other long-lived assets whenever events and changes in circumstances, such as reductions in demand or significant economic slowdowns in the industry, indicate that the carrying amount of an asset may not be fully recoverable. When indicators of impairment are present, the carrying values of the asset group are evaluated in relation to the future undiscounted cash flows of the underlying business. The net book value of the underlying asset is adjusted to fair value if the sum of the expected discounted cash flows is less than book value. Fair values are based on estimates of market prices and assumptions concerning the amount and timing of estimated future cash flows and assumed discount rates, reflecting varying degrees of perceived risk.

The impairment assessment of goodwill and other long-lived assets involves significant estimates and assumptions, which may be unpredictable and inherently uncertain. These estimates and assumptions include identification of reporting units and asset groups, long-term growth rates, profitability, estimated useful lives, comparable market multiples, and discount rates. Any changes in these assumptions could impact the result of the impairment assessment. There was no impairment of goodwill or other long-lived assets during fiscal 2018, 2017 and 2016.

Other Assets

The Company holds non-marketable equity securities as part of its strategic investments portfolio. During the first quarter of 2018, the Company adopted Accounting Standards Update No. 2016-01, "Recognition and Measurement of Financial Assets and Financial Liabilities," which revises the classification and measurement of financial instruments. Upon adoption of this standard, the Company now classifies its cost method investments as equity securities without readily determinable fair values and measures these investments at cost, less any impairment, adjusted for observable price changes. These investments are valued using significant unobservable inputs or data in an inactive market and the valuation requires the Company's judgment due to the absence of market prices and inherent lack of liquidity. The estimated fair value is based on quantitative and qualitative factors including, but not limited to, subsequent financing activities by the investee and projected discounted cash flows. At December 29, 2018, other assets consisted primarily of equity securities without readily determinable fair values and an equity method investment totaling $15.1 million. There was no adjustment recorded to the carrying value of the Company's equity securities without readily determinable fair values as a result of the adoption of ASU 2016-01. At December 30, 2017, other assets consisted primarily of cost method investments and an equity method investment totaling $14.2 million.

Financial Instruments and Hedging Activities

The Company utilizes derivative instruments to hedge specific financial risks including foreign exchange risk. The Company does not engage in speculative hedging activity. In order to account for a derivative instrument as a hedge, specific criteria must be met, including: (i) ensuring at the inception of the hedge that formal documentation exists for both the hedging relationship and the entity’s risk management objective and strategy for undertaking the hedge and (ii) at the inception of the hedge and on an ongoing basis, the hedging relationship is expected to be highly effective in achieving offsetting changes in fair value attributed to the hedged risk during the period that the hedge is designated. Further, an assessment of effectiveness is required whenever financial statements or earnings are reported. Absent meeting these criteria, changes in fair value are recognized in other income, net, in the consolidated statements of income. Once the underlying forecasted transaction is realized, the gain or loss from the derivative designated as a hedge of the transaction is reclassified from accumulated other comprehensive income (loss) to the statement of income, in revenue or cost of revenue.

Fair Value Measurements

The Company accounts for certain assets and liabilities at fair value. The fair value is established based on a three-tier fair value hierarchy, which prioritizes the inputs used in measuring fair value. These tiers include:

•Level 1 - observable inputs such as quoted prices for identical instruments in active markets;


•	Level 2 - inputs other than quoted prices in active markets that are either directly or indirectly observable; and


•	Level 3 - unobservable inputs in which little or no market data exists, therefore requiring an entity to develop its own assumptions.

Stock-Based Compensation

The Company accounts for stock-based compensation through recognition of the fair value of the stock-based compensation as a charge against earnings. The fair value of employee stock options is estimated at the grant date using the Black-Scholes option-pricing model. The fair value for time-based restricted stock units and performance-based restricted stock units is based on the closing share price of the Company's common stock on the date of grant. For performance-based restricted stock units, the compensation cost is recognized based on the number of units expected to vest upon the achievement of the performance conditions. The Company recognizes stock-based compensation as an expense on a straight-line basis, over the requisite service period. The Company accounts for forfeitures as they occur, rather than applying an estimated forfeiture rate, following its adoption of ASU No. 2016-09 in the first quarter of 2017.

Research and Development

Costs incurred in the research and development of the Company’s products are expensed as incurred.

Advertising Expense

The Company expenses advertising costs as they are incurred. During the years ended December 29, 2018, December 30, 2017 and December 31, 2016 advertising expense totaled $114.0 million, $91.8 million and $64.4 million, respectively, and are recorded within the selling and marketing expenses line item.

Income Taxes

Deferred tax assets and liabilities are determined based on the difference between the financial statement and tax basis using enacted tax rates in effect in the years in which those temporary differences are expected to be recovered or settled in each jurisdiction. A valuation allowance is provided if, based upon the weight of available evidence, it is more likely than not that the related benefits will not be realized. The Company regularly reviews the deferred tax assets for recoverability considering historical profitability, projected future taxable income, future reversals of existing taxable temporary differences, as well as feasible tax planning strategies in each jurisdiction. As of December 29, 2018, December 30, 2017 and December 30, 2016, the Company recorded a valuation allowance of $1.1 million, $0.8 million and $0.0 million, respectively, for certain foreign deferred tax assets for which the Company believes do not meet the "more likely than not" criteria for recognition.

The Company reports a liability for unrecognized tax benefits resulting from uncertain tax positions taken or expected to be taken in a tax return. The Company recognizes interest and penalties, if any, related to unrecognized tax benefits in the income tax provision.

On December 22, 2017, the Tax Cuts and Jobs Act of 2017 (the "Act") was signed into law making significant changes to the Internal Revenue Code. Effective for the Company’s 2018 tax year, the Act reduces the statutory federal corporate tax rate from 35% to 21% and implements certain additional provisions including the Global Intangible Low-Taxed Income ("GILTI") inclusion and the Foreign Derived Intangible Income ("FDII") deduction. Upon the enactment of the Act in December 2017, the Company recorded a one-time provisional income tax provision of $11.9 million in the fourth quarter of 2017 which included a provisional amount of $8.9 million related to the remeasurement of certain deferred tax assets and liabilities based on the tax rates at which they are expected to reverse in the future and $3.0 million related to the one-time transition tax on the mandatory deemed repatriation of foreign earnings. On December 22, 2017, the SEC staff issued Staff Accounting Bulletin No. 118 ("SAB 118") to address the application of U.S. GAAP in situations when a registrant does not have the necessary information available, prepared, or analyzed (including computations) in reasonable detail to complete the accounting for certain income tax effects of the Act. In accordance with SAB 118, during the fourth quarter of 2018, the Company finalized its analysis of the income tax effects of the Act and there were no material adjustments to the provisional amounts recorded.

Concentration of Credit Risk and Significant Customers

Financial instruments which potentially expose the Company to concentrations of credit risk consist of accounts receivable. Management believes its credit policies are prudent and reflect normal industry terms and business risk. At December 29, 2018, two customers accounted for a total of 23.1% of the Company's accounts receivable balance. At December 30, 2017, one customer accounted for a total of11.5% of the Company's accounts receivable balance. For the fiscal year ended December 29, 2018 and December 30, 2017, the Company generated 17.3% and 13.5%, respectively, of total revenue from one of its retailers (Amazon). For the fiscal year ended December 31, 2016 the Company generated 12.9%, 12.3% and 10.4% of total revenue from its distributor in Japan, Sales On Demand Corporation ("SODC"), Robopolis SAS, a network of affiliated European distributors ("Robopolis") and Amazon, respectively.

The Company maintains its cash in bank deposit accounts and money market funds at high quality financial institutions. The individual balances, at times, may exceed federally insured limits.

Net Income Per Share

Basic income per share is calculated using the Company's weighted-average outstanding common shares. Diluted income per share is calculated using the Company's weighted-average outstanding common shares including the dilutive effect of stock awards as determined under the treasury stock method. The following table presents the calculation of both basic and diluted net income per share:



	Fiscal Year Ended
	December 29, 2018		December 30, 2017		December 31, 2016
Net income	$	87,992	$	50,964	$	41,939
Weighted-average shares outstanding	27,692		27,611		27,698
Dilutive effect of employee stock options and restricted stock units	948		1,142		594
Diluted weighted-average shares outstanding	28,640		28,753		28,292
Basic income per share	$	3.18	$	1.85	$	1.51
Diluted income per share	$	3.07	$	1.77	$	1.48

Restricted stock units and stock options representing approximately 0.0 million, 0.0 million and 0.4 million shares of common stock for the fiscal years ended December 29, 2018, December 30, 2017 and December 31, 2016, respectively, were excluded from the computation of diluted earnings per share as their effect would have been antidilutive.

Recently Adopted Accounting Standards

In February 2018, the Financial Accounting Standards Board ("FASB") issued Accounting Standards Update ("ASU") No. 2018-02, "Reclassification of Certain Tax Effects from Accumulated Other Comprehensive Income," which provides an option to reclassify stranded tax effects within accumulated other comprehensive income to retained earnings in each period in which the effect of the change in the U.S. federal corporate income tax rate under the Tax Cuts and Jobs Act is recorded. This guidance is effective for fiscal years beginning after December 15, 2018, and interim periods within those fiscal years, with early adoption permitted. During the first quarter of 2018, the Company early adopted this standard, which did not have a material impact on the Company's consolidated financial statements and related disclosures.

In August 2017, the FASB issued ASU No. 2017-12, "Derivatives and Hedging," that was created to better align accounting rules with a company’s risk management activities, better reflect the economic results of hedging in the financial statements, and simplify hedge accounting treatment. The guidance is effective for fiscal years beginning after December 15, 2018, including interim periods within those fiscal years, with early adoption permitted. For cash flow hedges existing at the adoption date, the standard requires adoption on a modified retrospective basis with a cumulative-effect adjustment to the consolidated balance sheet as of the beginning of the year of adoption. During the fourth quarter of 2018, the Company early adopted this standard, which did not have a material impact on the Company's consolidated financial statements. The amended guidance requires modification to existing disclosure requirements on a prospective basis which have been updated in Note 10, "Derivative Instruments and Hedging."

In March 2017, the FASB issued ASU No. 2017-08, "Receivables – Nonrefundable Fees and Other Costs," which shortens the amortization period of certain callable debt securities held at a premium. The guidance is effective for fiscal years beginning after December 15, 2018, including interim periods within those fiscal years, with early adoption permitted. During the fourth quarter of 2018, the Company early adopted this standard, which did not have a material impact on the Company's consolidated financial statements and related disclosures.

In October 2016, FASB issued ASU No. 2016-16, "Income Taxes: Intra-Entity Transfers of Assets Other Than Inventory." ASU 2016-16 clarifies the accounting for the current and deferred income taxes for an intra-entity transfer of an asset other than inventory. ASU 2016-16 is effective for fiscal years beginning after December 15, 2017. During the first quarter of 2018, the Company adopted this standard, which did not have a material impact on the Company's consolidated financial statements and related disclosures.

In January 2016, the FASB issued ASU No. 2016-01, "Recognition and Measurement of Financial Assets and Financial Liabilities," as amended by ASU No. 2018-03 in February 2018, which revises various aspects of the recognition, measurement, presentation and disclosure of financial instruments. The standard requires that marketable equity investments be measured at fair value with changes to fair value recognized in net income. ASU No. 2016-01 also provides a new measurement alternative for non-marketable equity investments that do not have a readily determinable fair value. Under the measurement alternative, investments are measured at cost, less any impairment, adjusted for changes from observable transactions for identical or similar investments of the same issuer. The Company adopted this guidance on December 31, 2017 and elected to record its non-marketable equity investments using the alternative measurement method, which did not have a material impact on the Company's consolidated financial statements and related disclosures.

In May 2014, the FASB issued ASU No. 2014-09, "Revenue from Contracts with Customers," ("ASC 606") which provides guidance for revenue recognition. The standard’s core principle is that a company will recognize revenue when it transfers promised goods or services to customers in an amount that reflects the consideration to which the company expects to be entitled in exchange for those goods or services. On December 31, 2017, the Company adopted the guidance using the modified retrospective method applied to those contracts that were not completed as of the adoption date. Under the modified retrospective method, the Company recognized the cumulative effect of the adoption and recorded a net increase of $1.0 million to the beginning retained earnings as of December 31, 2017. See Note 3, "Revenue Recognition," for the required disclosures related to the impact of adopting this standard and a discussion of the Company's updated policies related to revenue recognition.

Recently Issued Accounting Standards

In August 2018, the FASB issued ASU No. 2018-15, "Intangibles - Goodwill and Other Internal-Use Software." The new standard aligns the requirements for capitalizing implementation costs incurred in a hosting arrangement that is a service contract with the requirements for capitalizing implementation costs incurred to develop or obtain internal-use software (and hosting arrangements that include an internal use software license). The amendments to this ASU are effective for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2019, with early adoption permitted. Implementation should be applied either retrospectively or prospectively to all implementation costs incurred after the date of adoption. The Company is currently evaluating the impact of the standard on its consolidated financial statements.

In August 2018, the FASB issued ASU No. 2018-13, "Fair Value Measurement: Disclosure Framework—Changes to the Disclosure Requirements for Fair Value Measurement." The amendment modifies disclosure requirements related to fair value measurement. The amendments to this ASU are effective for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2019. Implementation on a prospective or retrospective basis varies by specific disclosure requirement. Early adoption is permitted. The standard also allows for early adoption of any removed or modified disclosures upon issuance of this ASU while delaying adoption of the additional disclosures until their effective date. The Company does not believe this amendment will have a material impact on its consolidated financial statements.

In June 2018, the FASB issued ASU No. 2018-07, "Compensation - Stock Compensation: Improvements to Nonemployee Share-Based Payment Accounting (Topic 718)." The amendments in ASU No. 2018-07 expand the scope of Topic 718 to include share-based payments issued to nonemployees for goods or services. The amendments in this ASU are effective for annual periods beginning after December 15, 2018 and interim periods within those annual periods. Early adoption is permitted. The Company does not believe this amendment will have a material impact on its consolidated financial statements.

In June 2016, the FASB issued ASU No. 2016-13, "Measurement of Credit Losses on Financial Instruments," which amends the impairment model by requiring entities to use a forward-looking approach based on expected losses rather than incurred losses to estimate credit losses on certain types of financial instruments. This may result in the earlier recognition of allowances for losses. The guidance is effective for fiscal years beginning after December 15, 2019, including interim periods within those fiscal years, with early adoption permitted. The Company is currently evaluating the impact of the standard on its consolidated financial statements.

In February 2016, the FASB issued ASU No. 2016-02, "Leases." ASU No. 2016-02 requires lessees to recognize the assets and liabilities on their balance sheet for the rights and obligations created by most leases and continue to recognize expenses on their income statements over the lease term. The guidance is effective for annual reporting periods beginning after December 15, 2018 and interim periods within those fiscal years, with early adoption permitted. In July 2018, the FASB issued ASU No. 2018-11, "Leases: Targeted Improvements," which provided either a modified retrospective transition approach with application in all comparative periods presented, or an alternative transition method, which permits a company to use its effective date as the date of initial application without restating comparative period financial statements. The Company expects to elect this alternative transition method and adopt the guidance prospectively. The Company also expects to elect the practical expedients allowed under the standard. The Company is in the process of aggregating and evaluating lease arrangements and implementing new processes and a lease accounting system. The Company expects the adoption will result in a material increase in the assets and liabilities upon adoption. The impact on the Company's results of operations and cash flows is not expected to be material.

From time to time, new accounting pronouncements are issued by FASB that are adopted by the Company as of the specified effective date. Unless otherwise discussed, the Company believes that recently issued standards, which are not yet effective, will not have a material impact on the Company’s consolidated financial statements upon adoption.

Revenue Recognition (Notes)

12 Months Ended

Dec. 29, 2018

Revenue Recognition and Deferred Revenue [Abstract]

Revenue Recognition, Policy [Policy Text Block]



3.	Revenue Recognition

The Company primarily derives its revenue from product sales. The Company sells products directly to consumers through on-line stores and indirectly through resellers and distributors. Revenue is recognized upon transfer of control of promised products or services to customers, generally as title and risk of loss pass, in an amount that reflects the consideration the Company expects to receive in exchange for those products or services. Taxes collected from customers, which are subsequently remitted to governmental authorities, are excluded from revenue. Shipping and handling expenses are considered fulfillment activities and are expensed as incurred.

The Company’s product portfolio includes various consumer robots, many of which are Wi-Fi connected. The consumer robots are generally highly dependent on, and interrelated with, the embedded software and cannot function without the software. As such, the consumer robots are accounted for as a single performance obligation, and the revenue is recognized at a point in time when the control is transferred to distributors, resellers or directly to end customers through online stores. For consumer robots with Wi-Fi capability ("connected robots"), each sale represents an arrangement with multiple promises consisting of the robot, an app, cloud services and potential future unspecified software upgrades. The Company has determined that the app, cloud services and potential future unspecified software upgrades represent one promised service to the customer to enhance the functionality and interaction with the robot (referred to collectively as "Cloud Services"). Under the previous revenue accounting standard, revenue allocated to the app and future unspecified software upgrades was deferred and recognized on a straight-line basis over the expected life of the connected robot.

Upon the adoption of ASU No. 2014-09, "Revenue from Contracts with Customers," ("ASC 606") as of the beginning of fiscal year 2018, the Company concluded that, on a quantitative and qualitative basis, the Cloud Services did not constitute a material performance obligation for the then existing products and, as such, these services were not considered a separate performance obligation that required allocation of transaction price.

During the third quarter of 2018, the Company launched Roomba i7 and i7+ which have the ability to learn, map and adapt to a home's floor plan. The Company has concluded that the Cloud Services related to these new products are a material performance obligation. For contracts that contain multiple performance obligations, the transaction price is allocated to each performance obligation based on a relative standalone selling price ("SSP"). The SSP reflects the Company's best estimate of what the selling prices of elements would be if they were sold regularly on a standalone basis. Revenue allocated to the robots is recognized at a point in time when control is transferred. Revenue allocated to the Cloud Services is deferred and recognized on a straight-line basis over the estimated period the software upgrades and services are expected to be provided. The transaction price allocated to performance obligations that are unsatisfied as of December 29, 2018 is not material.

The Company’s products generally carry a one-year limited warranty (with the exception of European consumer products, which typically have a two-year warranty period) that promises customers that delivered products are as specified. The Company does not consider these assurance-type warranties as a separate performance obligation and therefore, the Company accounts for such warranties under ASC 460, "Guarantees."

Significant Judgments

The Company provides limited rights of returns for direct-to-consumer sales generated through its on-line stores as well as certain resellers and distributors. In addition, the Company may provide other credits or incentives, including price protection, which are accounted for as variable consideration when estimating the amount of revenue to recognize. Where appropriate, these estimates take into consideration relevant factors such as the Company’s historical experience, current contractual requirements, specific known market events and trends and forecasted customer buying and payment patterns. Overall, these reserves reflect the Company’s best estimates, and the actual amounts of consideration ultimately received may differ from the Company’s estimates. Returns and credits are estimated at contract inception and updated at the end of each reporting period as additional information becomes available and only to the extent that it is probable that a significant reversal of any incremental revenue will not occur. As of December 29, 2018, the Company has reserves for product returns of $53.9 million and other credits and incentives of $97.7 million. As of December 30, 2017, the Company had reserves for product returns of $42.7 million and other credits and incentives of $61.4 million.

Disaggregation of Revenue

The following table provides information about disaggregated revenue by geographical region for the year ended December 29, 2018 (in thousands):



	December 29, 2018
Americas	$	610,294
EMEA	311,659
APAC	170,631
Total revenue	$	1,092,584

Contract Balances

The following table provides information about receivables and contract liabilities from contracts with customers (in thousands):



	December 29, 2018 (closing balance)		December 31, 2017 (opening balance)
Accounts receivable, net	$	162,166	$	141,637
Contract liabilities	5,756		6,685

The Company invoices customers based upon contractual billing schedules, and accounts receivable are recorded when the right to consideration becomes unconditional. Contract liabilities primarily relate to prepayments received from customers in advance of product shipments. The change in the opening and closing balances of the Company’s contract assets and contract liabilities primarily results from the timing difference between the Company’s performance and the customer’s payment. During the year ended December 29, 2018, the Company recognized $6.7 million of the opening contract liability balance as revenue upon transfer of the products to customers. Revenue recognized during the year ended December 29, 2018 related to performance obligations satisfied in a prior period is not material.

Practical Expedients and Exemptions

The Company generally expenses sales commissions when incurred because the amortization period is generally one year or less. These costs are recorded within sales and marketing expenses.

The Company does not assess whether a prepayment received represents a significant financing component as the period between when the payment is received and the transfer of the products to the customer is generally one year or less.

The Company does not disclose the value of unsatisfied performance obligations for contracts with an original expected duration of one year or less.

Financial Statement Impact of Adopting ASC 606

The Company adopted ASC 606 using the modified retrospective method. The cumulative effect of applying the new guidance to all contracts with customers that were not completed as of December 30, 2017 was recorded as an increase of $1.0 million to retained earnings as of the adoption date. The adoption of the new guidance had an immaterial impact to the Company's consolidated balance sheet and statement of income as of and for the year ended December 29, 2018.

Business Combinations (Notes)

12 Months Ended

Dec. 29, 2018

Business Combinations [Abstract]

Business Combinations



4.	Business Combinations

Acquisition of Robopolis

On October 2, 2017, the Company closed the acquisition of its largest European distributor, Robopolis SAS, a French company ("Robopolis"), subsequently renamed iRobot France SAS. The acquisition will better enable the Company to maintain its leadership position and grow its business in several Western European countries through direct control of pre- and post-sales market activities including sales, marketing, branding, channel relationships and customer service. The initial purchase price was approximately $170.1 million in cash, net of acquired cash of $38.0 million, subject to the finalization of the working capital adjustment in accordance with the stock purchase agreement. During the first quarter of 2018, the working capital adjustment was finalized and resulted in a reduction in the purchase price of $0.7 million. During the fourth quarter of 2018, the Company finalized the allocation of the purchase price and recorded a $1.5 million adjustment for uncertain pre-acquisition income tax positions in various taxing jurisdictions against goodwill. The acquisition was a stock purchase. The results of operations for this acquisition have been included in the Company’s operating results since the acquisition date.

The following table summarizes the final allocation of the purchase price (in thousands):



Cash	$	37,981
Accounts receivable, net (1)	21,426
Inventory	36,304
Goodwill	80,419
Intangible assets	36,597
Other assets	2,456
Total assets	215,183

Accounts payable	(29,391		)
Accrued expenses	(3,376		)
Deferred tax liabilities	(10,864		)
Other liabilities	(2,138		)
Total liabilities assumed	(45,769		)
Net assets acquired	$	169,414

(1) The accounts receivable balance includes reserves for product returns, discounts and promotions assumed as part of the acquisition.

The following table reflects the fair value of the acquired identifiable intangible assets and related estimates of useful lives (in thousands):



	Useful Life	Fair Value
Reacquired distribution rights	2.25 years	$	29,296
Customer relationships	14 years	7,029
Non-competition agreements	3 years	272
Total		$	36,597

Acquisition of Sales On Demand Corporation

On April 3, 2017, the Company closed its acquisition of the iRobot-related distribution business of Sales On Demand Corporation ("SODC"), iRobot Japan G.K., for approximately $16.6 million in cash, equal to the book value of the acquired assets. The acquisition will better enable the Company to maintain its leadership position and accelerate the growth of its business in Japan through direct control of pre- and post-sales market activities including sales, marketing, branding, channel relationships and customer service. It also expands the Company's presence and customer outreach opportunities in Japan. The acquisition was a stock purchase. The results of operations for this acquisition have been included in the Company's operating results since the acquisition date.

During the three months ended September 30, 2017, the Company finalized the purchase price allocation and made measurement period adjustments to the provisional amounts reported as the estimated fair values of assets acquired. These measurement period adjustments resulted in a $2.2 million non-taxable gain on business acquisition which represents the excess of the fair value of the net assets acquired over the purchase price. The gain on business acquisition was recorded within other income, net in the consolidated statements of income. The Company believes that the gain on business acquisition was due to the transaction not being subjected to a competitive bidding process and the purchase price being determined based on the net book value of the net assets acquired.

The following table summarizes the final allocation of the purchase price (in thousands):



Cash	$	125
Accounts receivable, net (1)	(5,496		)
Inventory	18,290
Other assets	2,065
Deferred tax assets, net	409
Goodwill	—
Intangible assets	8,640
Total assets acquired	24,033

Accrued expenses and other current liabilities	(4,450		)
Other liabilities	(691		)
Total liabilities assumed	(5,141		)
Net assets acquired	$	18,892
Gain on business acquisition	(2,243		)
Total purchase price	$	16,649

(1) The accounts receivable balance reflects reserves for product returns, discounts and promotions assumed as part of the acquisition.

The following table reflects the fair value of the acquired identifiable intangible assets and related estimates of useful lives (in thousands):

Pro Forma Results (Unaudited)

The following table shows unaudited pro forma results of operations as if the Company had acquired Robopolis on January 3, 2016 (in thousands, except per share amounts):



	Fiscal Year Ended
	December 29, 2018		December 30, 2017		December 31, 2016
Revenue	$	1,092,584	$	901,612	$	718,917
Net income	87,992		51,887		53,320
Net income per share:
Basic income per share	$	3.18	$	1.88	$	1.93
Diluted income per share	$	3.07	$	1.80	$	1.88

The Company has not furnished pro forma financial information relating to its acquisition of SODC, because such information is not material, individually or in the aggregate, to its financial results. The unaudited pro forma results of operations are not necessarily indicative of the actual results that would have occurred had the transactions taken place at the beginning of the periods indicated.

Goodwill and other intangible assets

12 Months Ended

Dec. 29, 2018

Goodwill and Intangible Assets Disclosure [Abstract]

Goodwill and other intangible assets



7.	Goodwill and other intangible assets

The following table summarizes the activity in the carrying amount of goodwill for fiscal years 2018 and 2017 (in thousands):



Balance as of December 31, 2016	$	41,041
Acquisitions (Note 4)	79,558
Effect of foreign currency translation	841
Balance as of December 30, 2017	121,440
Purchase accounting adjustments (Note 4)	830
Effect of foreign currency translation	(3,374		)
Balance as of December 29, 2018	$	118,896

Intangible assets at December 29, 2018 and December 30, 2017 consisted of the following (in thousands):



	December 29, 2018						December 30, 2017
	Cost		Accumulated Amortization		Net		Cost		Accumulated Amortization		Net
Completed technology	$	26,900	$	21,607	$	5,293	$	26,900	$	18,150	$	8,750
Tradename	100		100		—		100		100		—
Customer relationships	11,291		1,365		9,926		11,594		418		11,176
Reacquired distribution rights	32,499		23,598		8,901		33,760		9,226		24,534
Non-competition agreements	263		110		153		275		23		252
Total	$	71,053	$	46,780	$	24,273	$	72,629	$	27,917	$	44,712

Amortization expense related to acquired intangible assets was $19.6 million, $13.1 million, and $3.5 million for the fiscal years ended December 29, 2018, December 30, 2017 and December 31, 2016, respectively.

The estimated future amortization expense related to current intangible assets in each of the five succeeding fiscal years is expected to be as follows (in thousands):



	Cost of Revenue		Operating Expenses		Total
2019	$	11,719	$	1,042	$	12,761
2020	900		1,020		1,920
2021	900		794		1,694
2022	675		794		1,469
2023	—		794		794
Thereafter	—		5,635		5,635
Total	$	14,194	$	10,079	$	24,273

Working Capital Facilities

12 Months Ended

Dec. 29, 2018

Debt Disclosure [Abstract]

Revolving Line of Credit



9.	Working Capital Facility

Credit Facility

In June 2018, the Company entered into a new agreement with Bank of America, N.A., increasing the amount of its unsecured revolving line of credit from $75.0 million to $150.0 million. As of December 29, 2018, the full amount was available for borrowing. The new revolving line of credit is available to fund working capital and other corporate purposes. The new agreement extends the term of the credit facilities to June 2023. The interest on loans under the credit facility accrues, at the Company's election, at either (1) LIBOR plus a margin, currently equal to 1.0%, based on the Company's ratio of indebtedness to Adjusted EBITDA (the "Eurodollar Rate"), or (2) the lender’s base rate. The lender’s base rate is equal to the highest of (1) the federal funds rate plus 0.5%, (2) the lender’s prime rate or (3) the Eurodollar Rate plus 1.0%.

As of December 29, 2018, the Company had no outstanding borrowings under its revolving credit facility. This credit facility contains customary terms and conditions for credit facilities of this type, including restrictions on the Company's ability to incur or guarantee additional indebtedness, create liens, enter into transactions with affiliates, make loans or investments, sell assets, pay dividends or make distributions on, or repurchase, the Company's stock, and consolidate or merge with other entities. In addition, the Company is required to meet certain financial covenants customary with this type of agreement, including maintaining a maximum ratio of indebtedness to Adjusted EBITDA and a minimum specified interest coverage ratio.

This credit facility contains customary events of default, including for payment defaults, breaches of representations, breaches of affirmative or negative covenants, cross defaults to other material indebtedness, bankruptcy and failure to discharge certain judgments. If a default occurs and is not cured within any applicable cure period or is not waived, the Company's obligations under the credit facility may be accelerated.

As of December 29, 2018, the Company was in compliance with all covenants under the revolving credit facility.

Derivative Instruments and Hedging Activities (Notes)

12 Months Ended

Dec. 29, 2018

Derivative Instruments and Hedging Activities Disclosure [Abstract]

Derivative Instruments and Hedging Activities



10.	Derivative Instruments and Hedging Activities

The Company operates internationally and, in the normal course of business, is exposed to fluctuations in foreign currency exchange rates. The foreign currency exposures typically arise from transactions denominated in currencies other than the functional currency of the Company's operations, primarily the Japanese Yen, Canadian dollar and the Euro. The Company uses derivative instruments that are designated in cash flow hedge relationships to reduce or eliminate the effects of foreign exchange rate changes on purchases and sales. These contracts have maturities of thirty-seven months or less. At December 29, 2018 and December 30, 2017, the Company had outstanding cash flow hedges with a total notional value of $366.7 million and $73.7 million, respectively.

The Company also enters into economic hedges that are not designated as hedges from an accounting standpoint to reduce or eliminate the effects of foreign exchange rate changes typically related to short term trade receivables and payables. These contracts typically have maturities of two months or less. At December 29, 2018 and December 30, 2017, the Company had outstanding economic hedges with a total notional value of $56.0 million and $36.6 million, respectively.

The fair values of derivative instruments are as follows (in thousands):



		Fair Value
	Classification	December 29, 2018		December 30, 2017
Derivatives not designated as hedging instruments:
Foreign currency forward contracts	Other current assets	$	551	$	413
Foreign currency forward contracts	Accrued expenses	—		221
Derivatives designated as cash flow hedges:
Foreign currency forward contracts	Other current assets	$	53	$	488
Foreign currency forward contracts	Other assets	172		116
Foreign currency forward contracts	Accrued expenses	335		279
Foreign currency forward contracts	Long-term liabilities	795		—

Gains (losses) associated with derivative instruments not designated as hedging instruments are as follows (in thousands):



		Fiscal year ended
	Classification	December 29, 2018		December 30, 2017
Gain (loss) recognized in income	Other income, net	$	1,568	$	(444	)

The following tables reflect the effect of derivatives designated as cash flow hedging for the years ended December 29, 2018 and December 30, 2017 (in thousands):



	Gain (loss) recognized in OCI on Derivative (1)
	Fiscal year ended
	December 29, 2018			December 30, 2017

Foreign currency forward contracts	$	(686	)	$	584


(1)	The amount represents the change in fair value of derivative contracts due to changes in spot rates.



	Gain (loss) recognized in earnings on cash flow hedging instruments
	December 29, 2018					December 30, 2017
	Revenue		Cost of revenue			Revenue		Cost of revenue
Consolidated statements of income in which the effects of cash flow hedging instruments are recorded	$	1,092,584	$	537,156		$	883,911	$	450,752

Gain or (loss) on cash flow hedging relationships:
Foreign currency forward contracts:
Amount of gain (loss) reclassified from AOCI into earnings	$	948	$	(386	)	$	320	$	(63	)

Fair Value Measurements

12 Months Ended

Dec. 29, 2018

Fair Value Disclosures [Abstract]

Fair Value Measurements



11.	Fair Value Measurements

The Company’s financial assets and liabilities measured at fair value on a recurring basis at December 29, 2018, were as follows (in thousands):



	Fair Value Measurements as of
	December 29, 2018
	Level 1		Level 2 (1)		Level 3 (2)
Assets:
Money market funds	$	3,730	$	—	$	—
Corporate and government bonds, $30,035 at cost (3)	—		29,605		—
Convertible note	—		—		2,000
Derivative instruments (Note 10)	—		776		—
Total assets measured at fair value	$	3,730	$	30,381	$	2,000

Liabilities:
Derivative instruments (Note 10)	$	—	$	1,130	$	—
Total liabilities measured at fair value	$	—	$	1,130	$	—

The Company’s financial assets and liabilities measured at fair value on a recurring basis at December 30, 2017, were as follows (in thousands):



	Fair Value Measurements as of
	December 30, 2017
	Level 1		Level 2 (1)		Level 3 (2)
Assets:
Money market funds	$	3,165	$	—	$	—
Corporate and government bonds, $37,767 at cost	—		37,225		—
Derivative instruments (Note 10)	—		1,017		—
Total assets measured at fair value	$	3,165	$	38,242	$	—

Liabilities:
Derivative instruments (Note 10)	$	—	$	500	$	—
Total liabilities measured at fair value	$	—	$	500	$	—


(1)	Level 2 fair value estimates are based on observable inputs other than quoted prices in active markets for identical assets and liabilities, quoted prices for identical or similar assets or liabilities in inactive markets, or other inputs that are observable or can be corroborated by observable market data for substantially the full term of the assets or liabilities.

(2)

Level 3 fair value estimates are based on inputs that are generally unobservable and typically reflect management’s estimates of assumptions that market participants would use in pricing the asset or liability. The fair values are therefore determined using model-based techniques, including option pricing and discounted cash flow models. Unobservable inputs used in the models are significant to the fair values of the assets and liabilities.


(3)	As of December 29, 2018, the Company’s investments had maturity dates ranging from March 2019 to March 2021.

During the year ended December 29, 2018, the Company invested in a non-marketable convertible note. The debt security is classified as available-for-sale and is included in short term investments on the consolidated balance sheet. The following table provides a summary of changes in fair value of our Level 3 investment for the year ended December 29, 2018 (in thousands):



Balance as of December 30, 2017	$	—
Investment	2,000
Balance as of December 29, 2018	$	2,000

- Definition

The entire disclosure for the fair value of financial instruments (as defined), including financial assets and financial liabilities (collectively, as defined), and the measurements of those instruments as well as disclosures related to the fair value of non-financial assets and liabilities. Such disclosures about the financial instruments, assets, and liabilities would include: (1) the fair value of the required items together with their carrying amounts (as appropriate); (2) for items for which it is not practicable to estimate fair value, disclosure would include: (a) information pertinent to estimating fair value (including, carrying amount, effective interest rate, and maturity, and (b) the reasons why it is not practicable to estimate fair value; (3) significant concentrations of credit risk including: (a) information about the activity, region, or economic characteristics identifying a concentration, (b) the maximum amount of loss the entity is exposed to based on the gross fair value of the related item, (c) policy for requiring collateral or other security and information as to accessing such collateral or security, and (d) the nature and brief description of such collateral or security; (4) quantitative information about market risks and how such risks are managed; (5) for items measured on both a recurring and nonrecurring basis information regarding the inputs used to develop the fair value measurement; and (6) for items presented in the financial statement for which fair value measurement is elected: (a) information necessary to understand the reasons for the election, (b) discussion of the effect of fair value changes on earnings, (c) a description of [similar groups] items for which the election is made and the relation thereof to the balance sheet, the aggregate carrying value of items included in the balance sheet that are not eligible for the election; (7) all other required (as defined) and desired information.

+ References + Details

Stockholders' Equity

12 Months Ended

Dec. 29, 2018

Equity [Abstract]

Stockholders' Equity



12.	Stockholders' Equity

Preferred Stock

The Company has authorized 5,000,000 shares of undesignated preferred stock with a par value of $0.01 per share. None of the preferred shares were issued and outstanding at December 29, 2018 and December 30, 2017.

Common Stock

Common stockholders are entitled to one vote for each share held and to receive dividends if and when declared by the Board of Directors and subject to and qualified by the rights of holders of the preferred stock. Upon dissolution or liquidation of the Company, holders of common stock will be entitled to receive all available assets subject to any preferential rights of any then outstanding preferred stock.

Share Repurchase Activity

On February 27, 2018, the Company's board of directors approved a stock repurchase program authorizing up to $50.0 million in share repurchases. This share repurchase program commenced on March 28, 2018 with an expiration date of December 28, 2018. As of June 30, 2018, the Company completed the repurchase program and repurchased 798,794 shares of common stock totaling $50.0 million.

On December 28, 2015, the Company announced a stock repurchase program, effective January 4, 2016 and ending on December 31, 2016, authorizing up to one million shares or $40 million in share repurchases. On March 1, 2016, the Company replaced the then-current stock repurchase program and entered into an accelerated share repurchase ("ASR") agreement to repurchase an aggregate of $85.0 million of common stock. During fiscal year 2016, the Company completed the repurchase program and repurchased 2,641,122 shares of common stock totaling $97.0 million.

Stock-Based Compensation

12 Months Ended

Dec. 29, 2018

Disclosure of Compensation Related Costs, Share-based Payments [Abstract]

Stock-Based Compensation



13.	Stock-Based Compensation

The Company has awards and options outstanding under four stock incentive plans: the 2005 Stock Option and Incentive Plan (the "2005 Plan"), the Evolution Robotics, Inc. 2007 Stock Plan (the "2007 Plan"), the 2015 Stock Option and Incentive Plan (the "2015 Plan") and the 2018 Stock Option and Incentive Plan (the "2018 Plan" and together with 2005 Plan, the 2007 Plan, and the 2015 Plan, the "Plans"). The 2018 Plan is the only one of the four plans under which new awards may currently be granted. Under the 2018 Plan, which became effective on May 23, 2018, 1,750,000 shares were initially reserved for issuance in the form of incentive stock options, non-qualified stock options, stock appreciation rights, restricted stock awards, restricted stock units, unrestricted stock awards, cash-based awards, and dividend equivalent rights. Stock awards returned to the Plans, with the exception of those issued under the 2005 Plan and the 2007 Plan, as a result of their expiration, cancellation or termination are automatically made available for issuance under the 2018 Plan. Eligibility for incentive stock options is limited to those individuals whose employment status would qualify them for the tax treatment associated with incentive stock options in accordance with the Internal Revenue Code of 1986, as amended. As of December 29, 2018, there were 1,623,670 shares available for future grant under the 2018 Plan. The Company recognized $25.8 million, $19.8 million and $16.0 million of stock-based compensation expense during the fiscal years ended December 29, 2018, December 30, 2017, and December 31, 2016, respectively. Stock-based compensation breaks down by expense classification as follows (in thousands):



	Fiscal Year Ended
	December 29, 2018		December 30, 2017		December 31, 2016
Cost of revenue	$	1,407	$	1,082	$	760
Research and development	7,494		5,009		3,646
Selling and marketing	2,842		2,571		2,008
General and administrative	14,061		11,089		9,581
Total	$	25,804	$	19,751	$	15,995

Stock Options

Options granted under the Plans are exercisable in full at any time subsequent to vesting, generally vest over four years, and expire five or ten years from the date of grant or, if earlier, 90 days from employee termination. The exercise price of stock options is typically equal to the Company's closing stock price on the date of grant.

As of December 29, 2018, the unamortized compensation costs associated with stock options was $1.8 million with a weighted-average remaining recognition period of 1.29 years.

The following table summarizes stock option activity for fiscal years 2018, 2017 and 2016:



	Number of Shares		Weighted Average Exercise Price		Weighted Average Remaining Contractual Term	Aggregate Intrinsic Value(1)
Outstanding at January 2, 2016	1,287,550		$	26.73
Granted	314,770		38.03
Exercised	(456,498	)	20.47
Canceled	(57,648	)	33.28
Outstanding at December 31, 2016	1,088,174		$	32.27
Granted	10,975		57.33
Exercised	(367,267	)	28.79
Canceled	(18,928	)	36.72
Outstanding at December 30, 2017	712,954		$	34.34
Granted	—		—
Exercised	(239,830	)	33.40
Canceled	(10,863	)	46.20
Outstanding at December 29, 2018	462,261		$	34.55	3.58 years	$21.6 million
Vested and expected to vest at December 29, 2018	462,261		$	34.55	3.58 years	$21.6 million
Exercisable as of December 29, 2018	317,997		$	33.10	3.26 years	$15.3 million

_________________________


(1)	The aggregate intrinsic value on the table above represents the difference between the Company's closing stock price on December 29, 2018 of $81.32 and the exercise price of the underlying in-the-money option.

There were no options granted for the fiscal year ended December 29, 2018. The fair value of each option grant for the fiscal years ended December 30, 2017, and December 31, 2016 was computed on the grant date using the Black-Scholes option-pricing model with the following assumptions:



	Fiscal Year Ended
	December 29, 2018	December 30, 2017	December 31, 2016
Risk-free interest rate	—	2.11%	1.17% — 1.89%
Expected dividend yield	—	—	—
Expected life	—	4.01 years	4.01 — 4.03 years
Expected volatility	—	38.0%	38.9% — 42.1%

The risk-free interest rate is derived from the average U.S. Treasury constant maturity rate, which approximates the rate in effect at the time of grant, commensurate with the expected life of the instrument. The dividend yield is zero based upon the fact the Company has never paid and has no present intention to pay cash dividends. The Company utilizes company specific historical data for purposes of establishing expected volatility and expected term.

During fiscal years 2018, 2017, and 2016, the total intrinsic value of stock options exercised was $14.9 million, $21.8 million, and $10.3 million, respectively.

The following table summarizes information about stock options outstanding at December 29, 2018:



	Options Outstanding				Options Exercisable
Range of Exercise Prices	Number Outstanding	Weighted Average Remaining Contractual Life	Weighted Average Exercise Price		Number Exercisable	Weighted Average Exercise Price
$ 3.54 - $ 22.86	46,918	1.55 years	$	19.84	46,918	$	19.84
26.59 - 32.38	83,084	3.51	30.98		62,968	31.05
33.14 - 33.14	85,984	4.19	33.14		48,436	33.14
33.29 - 34.30	71,864	3.26	34.07		57,664	34.07
35.43 - 37.08	28,276	2.52	35.69		28,276	35.69
37.62 - 37.62	78,419	4.44	37.62		38,874	37.62
39.09 - 39.09	23,367	4.70	39.09		7,566	39.09
43.35 - 43.35	19,194	2.19	43.35		19,194	43.35
57.33 - 57.33	8,046	5.19	57.33		2,985	57.33
58.55 - 58.55	17,109	4.95	58.55		5,116	58.55
$ 3.54 - $58.55	462,261	3.58 years	$	34.55	317,997	$	33.10

Time-based Restricted Stock Units

Time-based restricted stock units entitle the holder to a specific number of shares of common stock upon vesting, typically over a four-year period. As of December 29, 2018, the unamortized compensation costs associated with restricted stock units was $44.0 million with a weighted-average remaining recognition period of 2.33 years.

The following table summarizes the time-based restricted stock unit activity for fiscal years 2018, 2017 and 2016:



	Number of Shares Underlying Restricted Stock		Weighted Average Grant Date Fair Value
Outstanding at January 2, 2016	933,877		$	31.42
Granted	458,237		37.93
Vested	(358,018	)	30.81
Forfeited	(98,917	)	32.13
Outstanding at December 31, 2016	935,179		$	35.07
Granted	396,164		72.63
Vested	(351,543	)	33.73
Forfeited	(41,347	)	39.52
Outstanding at December 30, 2017	938,453		$	51.24
Granted	307,614		81.55
Vested	(351,816	)	47.30
Forfeited	(38,362	)	60.62
Outstanding at December 29, 2018	855,889		$	63.32

The aggregate intrinsic value of outstanding time-based restricted stock units at December 29, 2018 was $69.6 million based on the Company's closing stock price on December 29, 2018 of $81.32, with a weighted average remaining contractual term of 1.40 years.

Performance-Based Restricted Stock Units

The Company grants performance-based restricted stock units ("PSUs") to certain of its employees. The PSUs have performance metrics based on financial performance of the Company measured at the end of a three-year performance period. For the 2017 and 2016 grant years, the performance metric for these awards is based on revenue, operating income and/or operating income percent, with a threshold requirement for a minimum amount of revenue growth. Starting in 2018, the Company has removed revenue as a performance metric in the PSU plan design and changed the payout metric from three-year cumulative operating income as a percentage of annual revenue to three-year cumulative operating income in dollars. The number of shares actually earned at the end of the three-year period will range from 0% to 200% of the target number of PSUs granted based on the Company’s performance against the performance conditions.

The unamortized fair value as of December 29, 2018 associated with performance based restricted stock units was $7.1 million with a weighted-average remaining recognition period of 1.24 years.

The following table summarizes the performance-based restricted stock unit activity for fiscal years 2018, 2017 and 2016:



	Number of Shares Underlying PSU (1)		Weighted Average Grant Date Fair Value
Outstanding at January 2, 2016	90,492		$	36.78
Granted	82,085		33.36
Vested	(5,625	)	34.30
Forfeited	(3,041	)	34.30
Outstanding at December 31, 2016	163,911		$	35.03
Granted	105,650		57.33
Vested	(24,792	)	43.35
Forfeited	(2,708	)	39.71
Outstanding at December 30, 2017	242,061		$	43.97
Granted	91,538		68.41
Vested	(56,259	)	34.30
Forfeited	(3,221	)	45.71
Outstanding at December 29, 2018	274,119		$	54.10

_________________________

(1) Includes the target number of PSUs.

The aggregate intrinsic value of outstanding PSUs was $22.3 million based on the Company's closing stock price on December 29, 2018 of $81.32 with a weighted average remaining contractual term of 1.24 years.

Employee Stock Purchase Plan

In May 2017, the Company’s stockholders approved the 2017 Employee Stock Purchase Plan ("ESPP"). Eligible employees may purchase the Company’s common stock through payroll deductions at a price equal to 85% of the lower of the fair market values of the stock as of the beginning or the end of six-month offering periods beginning November 15 and May 15 of each year. An employee’s payroll deductions under the ESPP are limited to 15% of the employee’s compensation, up to $4,000 each period, for the purchase of common stock not to exceed 1,000 shares per offering period. As of December 29, 2018, there were 631,542 shares reserved for future issuance under the ESPP. The Company recognized $1.0 million and $0.1 million of stock-based compensation expense during the fiscal years ended December 29, 2018 and December 30, 2017, respectively.

Commitments and Contingencies

12 Months Ended

Dec. 29, 2018

Commitments and Contingencies Disclosure [Abstract]

Commitments and Contingencies



14.	Commitments and Contingencies

Legal Proceedings

From time to time and in the ordinary course of business, the Company is subject to various claims, charges and litigation. The outcome of litigation cannot be predicted with certainty and some lawsuits, claims or proceedings may be disposed of unfavorably to us, which could materially affect our financial condition or results of operations.

Lease Obligations

The Company leases its facilities. Rental expense under operating leases for fiscal years 2018, 2017 and 2016 amounted to $12.9 million, $8.9 million, and $6.0 million, respectively. Future minimum rental payments under operating leases were as follows as of December 29, 2018 (in thousands):



	Operating Leases
2019	$	7,848
2020	7,397
2021	7,345
2022	7,292
2023	7,021
Thereafter	34,806
Total minimum lease payments	$	71,709

Outstanding Purchase Orders

At December 29, 2018, we had outstanding purchase orders aggregating approximately $113.6 million. The purchase orders, the majority of which are with our contract manufacturers for the purchase of inventory in the normal course of business, are for manufacturing and non-manufacturing related goods and services, and are generally cancelable without penalty. In circumstances where we determine that we have financial exposure associated with any of these commitments, we record a liability in the period in which that exposure is identified.

Guarantees and Indemnification Obligations

The Company enters into standard indemnification agreements in the ordinary course of business. Pursuant to these agreements, the Company indemnifies and agrees to reimburse the indemnified party for losses incurred by the indemnified party, generally the Company’s customers, in connection with any patent, copyright, trade secret or other proprietary right infringement claim by any third party. The term of these indemnification agreements is generally perpetual any time after execution of the agreement. The maximum potential amount of future payments the Company could be required to make under these indemnification agreements is unlimited. The Company has never incurred costs to defend lawsuits or settle claims related to these indemnification agreements. As a result, the Company believes the estimated fair value of these agreements is minimal. Accordingly, the Company has no liabilities recorded for these agreements as of December 29, 2018 and December 30, 2017, respectively.

Warranty

The Company provides warranties on most products and has established a reserve for warranty obligations based on estimated warranty costs. The reserve is included as part of accrued expenses (Note 8) in the accompanying consolidated balance sheets.

Activity related to the warranty accrual was as follows (in thousands):



	Fiscal Year Ended
	December 29, 2018			December 30, 2017			December 31, 2016
Balance at beginning of period	$	11,264		$	8,464		$	6,907
Liability assumed (1)	—			2,186			—
Provision	10,798			8,591			7,494
Warranty usage (2)	(10,098		)	(7,977		)	(5,937		)
Balance at end of period	$	11,964		$	11,264		$	8,464

__________________________________


(1)	Warranty assumed as part of the acquisition of the iRobot-related distribution business of Sales On Demand Corporation.


(2)	Warranty usage includes costs incurred for warranty obligations.

Income Taxes

12 Months Ended

Dec. 29, 2018

Income Tax Disclosure [Abstract]

Income Taxes



16.	Income Taxes

Income (loss) before provision for income taxes was as follows (in thousands):



	Fiscal Year Ended
	December 29, 2018			December 30, 2017		December 31, 2016
Domestic	113,078			71,382		61,706
Foreign	(4,456		)	4,984		(345		)
Income before income taxes	$	108,622		$	76,366	$	61,361

The components of income tax expense were as follows (in thousands):



	Fiscal Year Ended
	December 29, 2018			December 30, 2017			December 31, 2016
Current
Federal	$	17,627		$	17,555		$	17,639
State	3,676			1,691			1,054
Foreign	10,732			7,355			310
Total current income tax provision	32,035			26,601			19,003
Deferred
Federal	$	(2,475	)	$	6,664		$	781
State	(1,149		)	(2,470		)	(95		)
Foreign	(7,781		)	(5,393		)	(267		)
Total deferred income tax provision	(11,405		)	(1,199		)	419
Total income tax provision	$	20,630		$	25,402		$	19,422

Due to the adoption of ASU 2016-09 in 2017, all excess tax benefits and deficiencies are recognized as income tax expense in the Company’s consolidated statement of income. This will result in increased volatility in the Company’s effective tax rate.

On December 22, 2017, the Tax Cuts and Jobs Act of 2017 (the "Act") was signed into law making significant changes to the Internal Revenue Code. Effective for the Company's 2018 tax year, the Act reduces the statutory federal corporate tax rate from 35% to 21% and implements certain additional provisions including the Global Intangible Low-Taxed Income ("GILTI") inclusion and the Foreign Derived Intangible Income ("FDII") deduction. Upon the enactment of the Act in December 2017, the Company recorded a one-time provisional income tax provision of $11.9 million in the fourth quarter of 2017 which included a provisional amount of $8.9 million related to the remeasurement of certain deferred tax assets and liabilities based on the tax rates at which they are expected to reverse in the future and $3.0 million related to the one-time transition tax on the mandatory deemed repatriation of foreign earnings. On December 22, 2017, the SEC staff issued Staff Accounting Bulletin No. 118 ("SAB 118") to address the application of U.S. GAAP in situations when a registrant does not have the necessary information available, prepared, or analyzed (including computations) in reasonable detail to complete the accounting for certain income tax effects of the Act. In accordance with SAB 118, during the fourth quarter of 2018, the Company finalized its analysis of the income tax effects of the Act and determined no material adjustments to the provisional amounts recorded were required.

The reconciliation of statutory federal income tax to actual tax expense is as follows (in thousands):



	Fiscal Year Ended
	December 29, 2018			December 30, 2017			December 31, 2016
Statutory federal income tax	$	22,812		$	26,728		$	21,476
Miscellaneous permanent items	1,837			2,979			516
State taxes (net of federal benefit)	4,312			2,089			1,360
Federal and state credits	(5,638		)	(4,486		)	(2,233		)
Domestic production activities deduction	—			(1,528		)	(1,731		)
Excess tax benefits relating to stock-based compensation	(6,529		)	(11,709		)	—
Tax Cuts and Jobs Act of 2017	2,127			11,861			—
Foreign-derived intangible income deduction	(2,678		)	—			—
EMEA business restructuring	2,292			—			—
Other	2,095			(532		)	34
	$	20,630		$	25,402		$	19,422

The components of net deferred tax assets were as follows (in thousands):



	December 29, 2018			December 30, 2017
Deferred tax assets
Reserves and accruals	$	27,991		$	24,315
Tax credits and net operating loss carryforwards	7,781			6,810
Property and equipment	1,360			1,382
Stock-based compensation	4,975			4,277
Gross deferred tax assets	42,107			36,784
Valuation allowance	(1,148		)	(800		)
Total deferred tax assets	40,959			35,984
Deferred tax liabilities
Intangible assets	7,317			13,419
Other	668			573
Total deferred tax liabilities	7,985			13,992
Net deferred tax assets	$	32,974		$	21,992

The Company intends to continue to invest all of its unremitted foreign earnings, as well as the capital in its foreign subsidiaries, indefinitely outside of the U.S. At December 29, 2018, the Company has immaterial unremitted foreign earnings and any unrecognized deferred tax liability on these unremitted earnings would be immaterial.

The Company has foreign net operating loss carryforwards of $3.4 million and $0.1 million as of December 29, 2018 and December 30, 2017, respectively. The Company has state research and development credit carryforwards of $10.7 million and $10.1 million as of December 29, 2018 and December 30, 2017, respectively, which expire from 2027 to 2033. Under the Internal Revenue Code and state law, certain substantial changes in the Company’s ownership could result in an annual limitation on the amount of these tax carryforwards which can be utilized in future years.

As of December 29, 2018, December 30, 2017 and December 31, 2016, the Company recorded a valuation allowance of $1.1 million, $0.8 million and $0.0 million, respectively, for certain foreign deferred tax assets for which the Company believes do not meet the "more likely than not" criteria for recognition.

A summary of the Company’s adjustments to its gross unrecognized tax benefits in the current year is as follows (in thousands):



	Fiscal Year Ended
	December 29, 2018			December 30, 2017			December 31, 2016
Balance at beginning of period	$	4,590		$	5,146		$	6,616
Increase for tax positions related to the current year	2,891			580			2,851
Increase for tax positions related to acquisition	1,493			—			—
Increase (decrease) for tax positions related to prior years	407			(523		)	(4,224		)
Decreases for settlements with applicable taxing authorities	(2,262		)	—			—
Decreases for lapses of statute of limitations	—			(613		)	(97		)
Balance at end of period	$	7,119		$	4,590		$	5,146

During the fourth quarter of 2018, the Company finalized the purchase accounting related to its acquisition of Robopolis and recorded a $1.5 million adjustment for uncertain pre-acquisition income tax positions in various taxing jurisdictions against goodwill. In addition, the Company recorded a charge of $2.3 million for estimated taxes associated with a restructuring of the EMEA business during fiscal 2018. The Company accrues interest and, if applicable, penalties for any uncertain tax positions as a component of income tax expense. As of December 29, 2018, December 30, 2017 and December 31, 2016 there were no material accrued interest or penalties.

The Company is subject to taxation in the United States (federal and state) and foreign jurisdictions. The statute of limitations for examinations by the Internal Revenue Service (the "IRS") is closed for fiscal years prior to 2014. The statute of limitations for examinations by state tax authorities is closed for fiscal years prior to 2013. Federal and state carryforward attributes that were generated prior to fiscal 2014 and 2013, respectively, may still be adjusted upon examination by the federal or state tax authorities if they either have been or will be used in a period for which the statute of limitations is still open. The Company is currently under examination by the IRS for the years 2014 and 2015. There are other ongoing audits in various other jurisdictions that are not material to the Company's financial statements. The Company regularly assesses the likelihood of adverse outcomes resulting from these examinations to determine the adequacy of its provision for income taxes. The Company continues to monitor the progress of ongoing discussions with tax authorities and the effect, if any, of the expected expiration of the statute of limitations in various taxing jurisdictions. The Company believes that an adequate provision has been made for any adjustments that may result from tax examinations. However, the outcome of tax audits cannot be predicted with certainty. If any issues addressed in the Company's tax audits are resolved in a manner not consistent with management's expectations, the Company could be required to adjust its provision for income taxes in the period such resolution occurs. Although the timing of resolution, settlement, and closure of audits is not certain, it is reasonably possible that certain U.S. federal and non-U.S. tax audits may be concluded within the next 12 months, which could increase or decrease the balance of the Company's gross unrecognized tax benefits. The Company does not expect a significant change in the amount of unrecognized tax benefits within the next 12 months. If all of the Company's unrecognized tax benefits as of December 29, 2018 were to become recognizable in the future, it would record a $7.4 million benefit, inclusive of interest, to the income tax provision.

Industry Segment, Geographic Information and Significant Customers

12 Months Ended

Dec. 29, 2018

Segment Reporting [Abstract]

Industry Segment, Geographic Information and Significant Customers



17.	Industry Segment, Geographic Information and Significant Customers

The Company operates as one operating segment. The Company's consumer robots products are offered to consumers through distributor and retail sales channels, as well as its on-line stores.

Geographic Information

For the fiscal years ended December 29, 2018, December 30, 2017 and December 31, 2016, sales to non-U.S. customers accounted for 48.7%, 48.8% and 51.2% of total revenue, respectively.

Significant Customers

For the fiscal years ended December 29, 2018 and December 30, 2017, the Company generated 17.3% and 13.5% of total revenue from one of its retailers (Amazon), respectively. For the fiscal year ended December 31, 2016, the Company generated 12.9%, 12.3% and 10.4% of total revenue from its distributor in Japan ("SODC"), a network of affiliated European distributors ("Robopolis") and Amazon, respectively. On April 3, 2017, the Company acquired the iRobot-related distribution business of SODC, and on October 2, 2017, the Company acquired Robopolis (see Note 4).

Summary of Significant Accounting Policies (Policies)

12 Months Ended

Dec. 29, 2018

Accounting Policies [Abstract]

Basis of Presentation

Basis of Presentation and Foreign Currency Translation

Use of Estimates

Fiscal Year-End

Business Combinations

Cash and Cash Equivalents

Short Term Investments



	December 29, 2018				December 30, 2017
	Cost		Fair Market Value		Cost		Fair Market Value
Corporate and government bonds	$	30,035	$	29,605	$	37,767	$	37,225
Convertible note	2,000		2,000		—		—
Total short term investments	$	32,035	$	31,605	$	37,767	$	37,225

Accounts receivable allowances

Inventory

Warranty

Property and Equipment



	Estimated Useful Life
Computer and research equipment	2-5 years
Furniture	5
Machinery	2-5
Tooling	2-5
Business applications software	3-7
Leasehold improvements	Lesser of economic benefit period or term of lease

Goodwill and Other Long-Lived Assets

Other Assets

Financial Instruments and Hedging Activities

Fair Value Measurements

•Level 1 - observable inputs such as quoted prices for identical instruments in active markets;


•	Level 2 - inputs other than quoted prices in active markets that are either directly or indirectly observable; and


•	Level 3 - unobservable inputs in which little or no market data exists, therefore requiring an entity to develop its own assumptions.

Stock-Based Compensation

Research and Development

Costs incurred in the research and development of the Company’s products are expensed as incurred.

Advertising Expense

Income Taxes

Concentration of Credit Risk and Significant Customers

The Company maintains its cash in bank deposit accounts and money market funds at high quality financial institutions. The individual balances, at times, may exceed federally insured limits.

Net Income Per Share



	Fiscal Year Ended
	December 29, 2018		December 30, 2017		December 31, 2016
Net income	$	87,992	$	50,964	$	41,939
Weighted-average shares outstanding	27,692		27,611		27,698
Dilutive effect of employee stock options and restricted stock units	948		1,142		594
Diluted weighted-average shares outstanding	28,640		28,753		28,292
Basic income per share	$	3.18	$	1.85	$	1.51
Diluted income per share	$	3.07	$	1.77	$	1.48

Recent Accounting Pronouncements

Recently Adopted Accounting Standards

Recently Issued Accounting Standards

Summary of Significant Accounting Policies (Tables)

12 Months Ended

Dec. 29, 2018

Accounting Policies [Abstract]

Components of available for sale securities

The fair value of investments is determined based on quoted market prices at the reporting date for those instruments. As of December 29, 2018 and December 30, 2017, investments consisted of (in thousands):



	December 29, 2018				December 30, 2017
	Cost		Fair Market Value		Cost		Fair Market Value
Corporate and government bonds	$	30,035	$	29,605	$	37,767	$	37,225
Convertible note	2,000		2,000		—		—
Total short term investments	$	32,035	$	31,605	$	37,767	$	37,225

Activity related to accounts receivable allowances was as follows (in thousands):



	Fiscal Year Ended
	December 29, 2018			December 30, 2017			December 31, 2016
Allowance for product returns
Balance at beginning of period	$	42,693		$	27,673		$	25,992
Acquired balance	—			6,088			—
Provision	68,476			54,981			33,992
Deduction	(56,164		)	(43,831		)	(28,826		)
Other adjustments	(1,085		)	(2,218		)	(3,485		)
Balance at end of period	$	53,920		$	42,693		$	27,673

Allowance for other credits and incentives
Balance at beginning of period	$	61,359		$	23,658		$	23,005
Acquired balance	—			11,932			—
Adjustment related to adoption of ASC 606	1,192			—			—
Provision	198,371			110,605			47,419
Deduction	(161,672		)	(81,269		)	(46,610		)
Other adjustments	(1,513		)	(3,567		)	(156		)
Balance at end of period	$	97,737		$	61,359		$	23,658

Property and equipment

Depreciation is computed using the straight-line method over the estimated useful lives as follows:



	Estimated Useful Life
Computer and research equipment	2-5 years
Furniture	5
Machinery	2-5
Tooling	2-5
Business applications software	3-7
Leasehold improvements	Lesser of economic benefit period or term of lease

Property and equipment consists of the following (in thousands):



	December 29, 2018		December 30, 2017
Computer and equipment	$	12,339	$	10,669
Furniture	5,231		4,120
Machinery	20,606		14,202
Tooling	39,675		31,783
Leasehold improvements	28,701		26,136
Business applications software	15,638		12,757
Subtotal	122,190		99,667
Less: accumulated depreciation	65,164		55,088
Property and equipment, net	$	57,026	$	44,579

Basic and diluted net income per share

The following table presents the calculation of both basic and diluted net income per share:



	Fiscal Year Ended
	December 29, 2018		December 30, 2017		December 31, 2016
Net income	$	87,992	$	50,964	$	41,939
Weighted-average shares outstanding	27,692		27,611		27,698
Dilutive effect of employee stock options and restricted stock units	948		1,142		594
Diluted weighted-average shares outstanding	28,640		28,753		28,292
Basic income per share	$	3.18	$	1.85	$	1.51
Diluted income per share	$	3.07	$	1.77	$	1.48

Revenue Recognition (Tables)

12 Months Ended

Dec. 29, 2018

Contract Balances [Abstract]

Disaggregation of Revenue [Table Text Block]

Disaggregation of Revenue

The following table provides information about disaggregated revenue by geographical region for the year ended December 29, 2018 (in thousands):



	December 29, 2018
Americas	$	610,294
EMEA	311,659
APAC	170,631
Total revenue	$	1,092,584

Contract with Customer, Asset and Liability [Table Text Block]

Contract Balances

The following table provides information about receivables and contract liabilities from contracts with customers (in thousands):



	December 29, 2018 (closing balance)		December 31, 2017 (opening balance)
Accounts receivable, net	$	162,166	$	141,637
Contract liabilities	5,756		6,685

Business Combinations (Tables)

12 Months Ended

Dec. 29, 2018

Business Combinations [Abstract]

Schedule of allocation of purchase price

The following table summarizes the final allocation of the purchase price (in thousands):



Cash	$	37,981
Accounts receivable, net (1)	21,426
Inventory	36,304
Goodwill	80,419
Intangible assets	36,597
Other assets	2,456
Total assets	215,183

Accounts payable	(29,391		)
Accrued expenses	(3,376		)
Deferred tax liabilities	(10,864		)
Other liabilities	(2,138		)
Total liabilities assumed	(45,769		)
Net assets acquired	$	169,414

The following table summarizes the final allocation of the purchase price (in thousands):



Cash	$	125
Accounts receivable, net (1)	(5,496		)
Inventory	18,290
Other assets	2,065
Deferred tax assets, net	409
Goodwill	—
Intangible assets	8,640
Total assets acquired	24,033

Accrued expenses and other current liabilities	(4,450		)
Other liabilities	(691		)
Total liabilities assumed	(5,141		)
Net assets acquired	$	18,892
Gain on business acquisition	(2,243		)
Total purchase price	$	16,649

(1) The accounts receivable balance reflects reserves for product returns, discounts and promotions assumed as part of the acquisition.

Schedule of acquired intangible assets

The following table reflects the fair value of the acquired identifiable intangible assets and related estimates of useful lives (in thousands):



	Useful Life	Fair Value
Reacquired distribution rights	2.25 years	$	29,296
Customer relationships	14 years	7,029
Non-competition agreements	3 years	272
Total		$	36,597

The following table reflects the fair value of the acquired identifiable intangible assets and related estimates of useful lives (in thousands):

Schedule of pro forma results

Pro Forma Results (Unaudited)

The following table shows unaudited pro forma results of operations as if the Company had acquired Robopolis on January 3, 2016 (in thousands, except per share amounts):



	Fiscal Year Ended
	December 29, 2018		December 30, 2017		December 31, 2016
Revenue	$	1,092,584	$	901,612	$	718,917
Net income	87,992		51,887		53,320
Net income per share:
Basic income per share	$	3.18	$	1.88	$	1.93
Diluted income per share	$	3.07	$	1.80	$	1.88

Goodwill and other intangible assets (Tables)

12 Months Ended

Dec. 29, 2018

Goodwill and Intangible Assets Disclosure [Abstract]

Schedule of goodwill

The following table summarizes the activity in the carrying amount of goodwill for fiscal years 2018 and 2017 (in thousands):



Balance as of December 31, 2016	$	41,041
Acquisitions (Note 4)	79,558
Effect of foreign currency translation	841
Balance as of December 30, 2017	121,440
Purchase accounting adjustments (Note 4)	830
Effect of foreign currency translation	(3,374		)
Balance as of December 29, 2018	$	118,896

Other intangible assets

Intangible assets at December 29, 2018 and December 30, 2017 consisted of the following (in thousands):



	December 29, 2018						December 30, 2017
	Cost		Accumulated Amortization		Net		Cost		Accumulated Amortization		Net
Completed technology	$	26,900	$	21,607	$	5,293	$	26,900	$	18,150	$	8,750
Tradename	100		100		—		100		100		—
Customer relationships	11,291		1,365		9,926		11,594		418		11,176
Reacquired distribution rights	32,499		23,598		8,901		33,760		9,226		24,534
Non-competition agreements	263		110		153		275		23		252
Total	$	71,053	$	46,780	$	24,273	$	72,629	$	27,917	$	44,712

Estimated future amortization expense related to current intangible assets

The estimated future amortization expense related to current intangible assets in each of the five succeeding fiscal years is expected to be as follows (in thousands):



	Cost of Revenue		Operating Expenses		Total
2019	$	11,719	$	1,042	$	12,761
2020	900		1,020		1,920
2021	900		794		1,694
2022	675		794		1,469
2023	—		794		794
Thereafter	—		5,635		5,635
Total	$	14,194	$	10,079	$	24,273

Derivative Instruments and Hedging Activities (Tables)

12 Months Ended

Dec. 29, 2018

Derivative Instruments and Hedging Activities Disclosure [Abstract]

Schedule of fair values of derivative instruments

The fair values of derivative instruments are as follows (in thousands):



		Fair Value
	Classification	December 29, 2018		December 30, 2017
Derivatives not designated as hedging instruments:
Foreign currency forward contracts	Other current assets	$	551	$	413
Foreign currency forward contracts	Accrued expenses	—		221
Derivatives designated as cash flow hedges:
Foreign currency forward contracts	Other current assets	$	53	$	488
Foreign currency forward contracts	Other assets	172		116
Foreign currency forward contracts	Accrued expenses	335		279
Foreign currency forward contracts	Long-term liabilities	795		—

Schedule of derivative instruments gain (loss)

Gains (losses) associated with derivative instruments not designated as hedging instruments are as follows (in thousands):



		Fiscal year ended
	Classification	December 29, 2018		December 30, 2017
Gain (loss) recognized in income	Other income, net	$	1,568	$	(444	)

The following tables reflect the effect of derivatives designated as cash flow hedging for the years ended December 29, 2018 and December 30, 2017 (in thousands):



	Gain (loss) recognized in OCI on Derivative (1)
	Fiscal year ended
	December 29, 2018			December 30, 2017

Foreign currency forward contracts	$	(686	)	$	584


(1)	The amount represents the change in fair value of derivative contracts due to changes in spot rates.



	Gain (loss) recognized in earnings on cash flow hedging instruments
	December 29, 2018					December 30, 2017
	Revenue		Cost of revenue			Revenue		Cost of revenue
Consolidated statements of income in which the effects of cash flow hedging instruments are recorded	$	1,092,584	$	537,156		$	883,911	$	450,752

Gain or (loss) on cash flow hedging relationships:
Foreign currency forward contracts:
Amount of gain (loss) reclassified from AOCI into earnings	$	948	$	(386	)	$	320	$	(63	)

Fair Value Measurements (Tables)

12 Months Ended

Dec. 29, 2018

Fair Value Disclosures [Abstract]

Schedule of financial assets and liabilities measured at fair value on a recurring basis

The Company’s financial assets and liabilities measured at fair value on a recurring basis at December 29, 2018, were as follows (in thousands):



	Fair Value Measurements as of
	December 29, 2018
	Level 1		Level 2 (1)		Level 3 (2)
Assets:
Money market funds	$	3,730	$	—	$	—
Corporate and government bonds, $30,035 at cost (3)	—		29,605		—
Convertible note	—		—		2,000
Derivative instruments (Note 10)	—		776		—
Total assets measured at fair value	$	3,730	$	30,381	$	2,000

Liabilities:
Derivative instruments (Note 10)	$	—	$	1,130	$	—
Total liabilities measured at fair value	$	—	$	1,130	$	—

The Company’s financial assets and liabilities measured at fair value on a recurring basis at December 30, 2017, were as follows (in thousands):



	Fair Value Measurements as of
	December 30, 2017
	Level 1		Level 2 (1)		Level 3 (2)
Assets:
Money market funds	$	3,165	$	—	$	—
Corporate and government bonds, $37,767 at cost	—		37,225		—
Derivative instruments (Note 10)	—		1,017		—
Total assets measured at fair value	$	3,165	$	38,242	$	—

Liabilities:
Derivative instruments (Note 10)	$	—	$	500	$	—
Total liabilities measured at fair value	$	—	$	500	$	—


(1)	Level 2 fair value estimates are based on observable inputs other than quoted prices in active markets for identical assets and liabilities, quoted prices for identical or similar assets or liabilities in inactive markets, or other inputs that are observable or can be corroborated by observable market data for substantially the full term of the assets or liabilities.

(2)


(3)	As of December 29, 2018, the Company’s investments had maturity dates ranging from March 2019 to March 2021.

Stock-Based Compensation (Tables)

12 Months Ended

Dec. 29, 2018

Disclosure of Compensation Related Costs, Share-based Payments [Abstract]

Summary of stock option plan activity

The following table summarizes stock option activity for fiscal years 2018, 2017 and 2016:



	Number of Shares		Weighted Average Exercise Price		Weighted Average Remaining Contractual Term	Aggregate Intrinsic Value(1)
Outstanding at January 2, 2016	1,287,550		$	26.73
Granted	314,770		38.03
Exercised	(456,498	)	20.47
Canceled	(57,648	)	33.28
Outstanding at December 31, 2016	1,088,174		$	32.27
Granted	10,975		57.33
Exercised	(367,267	)	28.79
Canceled	(18,928	)	36.72
Outstanding at December 30, 2017	712,954		$	34.34
Granted	—		—
Exercised	(239,830	)	33.40
Canceled	(10,863	)	46.20
Outstanding at December 29, 2018	462,261		$	34.55	3.58 years	$21.6 million
Vested and expected to vest at December 29, 2018	462,261		$	34.55	3.58 years	$21.6 million
Exercisable as of December 29, 2018	317,997		$	33.10	3.26 years	$15.3 million

_________________________


(1)	The aggregate intrinsic value on the table above represents the difference between the Company's closing stock price on December 29, 2018 of $81.32 and the exercise price of the underlying in-the-money option.

Fair value of each option grant computed on the grant date

The fair value of each option grant for the fiscal years ended December 30, 2017, and December 31, 2016 was computed on the grant date using the Black-Scholes option-pricing model with the following assumptions:



	Fiscal Year Ended
	December 29, 2018	December 30, 2017	December 31, 2016
Risk-free interest rate	—	2.11%	1.17% — 1.89%
Expected dividend yield	—	—	—
Expected life	—	4.01 years	4.01 — 4.03 years
Expected volatility	—	38.0%	38.9% — 42.1%

Summary of information about stock options outstanding



	Options Outstanding				Options Exercisable
Range of Exercise Prices	Number Outstanding	Weighted Average Remaining Contractual Life	Weighted Average Exercise Price		Number Exercisable	Weighted Average Exercise Price
$ 3.54 - $ 22.86	46,918	1.55 years	$	19.84	46,918	$	19.84
26.59 - 32.38	83,084	3.51	30.98		62,968	31.05
33.14 - 33.14	85,984	4.19	33.14		48,436	33.14
33.29 - 34.30	71,864	3.26	34.07		57,664	34.07
35.43 - 37.08	28,276	2.52	35.69		28,276	35.69
37.62 - 37.62	78,419	4.44	37.62		38,874	37.62
39.09 - 39.09	23,367	4.70	39.09		7,566	39.09
43.35 - 43.35	19,194	2.19	43.35		19,194	43.35
57.33 - 57.33	8,046	5.19	57.33		2,985	57.33
58.55 - 58.55	17,109	4.95	58.55		5,116	58.55
$ 3.54 - $58.55	462,261	3.58 years	$	34.55	317,997	$	33.10

Activities relating to time based restricted stock units

The following table summarizes the time-based restricted stock unit activity for fiscal years 2018, 2017 and 2016:



	Number of Shares Underlying Restricted Stock		Weighted Average Grant Date Fair Value
Outstanding at January 2, 2016	933,877		$	31.42
Granted	458,237		37.93
Vested	(358,018	)	30.81
Forfeited	(98,917	)	32.13
Outstanding at December 31, 2016	935,179		$	35.07
Granted	396,164		72.63
Vested	(351,543	)	33.73
Forfeited	(41,347	)	39.52
Outstanding at December 30, 2017	938,453		$	51.24
Granted	307,614		81.55
Vested	(351,816	)	47.30
Forfeited	(38,362	)	60.62
Outstanding at December 29, 2018	855,889		$	63.32

Activities relating to performance based restricted stock units

The following table summarizes the performance-based restricted stock unit activity for fiscal years 2018, 2017 and 2016:



	Number of Shares Underlying PSU (1)		Weighted Average Grant Date Fair Value
Outstanding at January 2, 2016	90,492		$	36.78
Granted	82,085		33.36
Vested	(5,625	)	34.30
Forfeited	(3,041	)	34.30
Outstanding at December 31, 2016	163,911		$	35.03
Granted	105,650		57.33
Vested	(24,792	)	43.35
Forfeited	(2,708	)	39.71
Outstanding at December 30, 2017	242,061		$	43.97
Granted	91,538		68.41
Vested	(56,259	)	34.30
Forfeited	(3,221	)	45.71
Outstanding at December 29, 2018	274,119		$	54.10

_________________________

(1) Includes the target number of PSUs.

Schedule of Share-based Payment Award, Employee Stock Purchase Plan, Valuation Assumptions [Table Text Block]

Employee Stock Purchase Plan

Commitments and Contingencies (Tables)

12 Months Ended

Dec. 29, 2018

Commitments and Contingencies Disclosure [Abstract]

Summary of future minimum rental payments under operating leases

Future minimum rental payments under operating leases were as follows as of December 29, 2018 (in thousands):



	Operating Leases
2019	$	7,848
2020	7,397
2021	7,345
2022	7,292
2023	7,021
Thereafter	34,806
Total minimum lease payments	$	71,709

Activity related to the warranty accrual was as follows (in thousands):



	Fiscal Year Ended
	December 29, 2018			December 30, 2017			December 31, 2016
Balance at beginning of period	$	11,264		$	8,464		$	6,907
Liability assumed (1)	—			2,186			—
Provision	10,798			8,591			7,494
Warranty usage (2)	(10,098		)	(7,977		)	(5,937		)
Balance at end of period	$	11,964		$	11,264		$	8,464

__________________________________


(1)	Warranty assumed as part of the acquisition of the iRobot-related distribution business of Sales On Demand Corporation.


(2)	Warranty usage includes costs incurred for warranty obligations.

Income Taxes (Tables)

12 Months Ended

Dec. 29, 2018

Income Tax Disclosure [Abstract]

Schedule of income (loss) before provision for income taxes

Income (loss) before provision for income taxes was as follows (in thousands):



	Fiscal Year Ended
	December 29, 2018			December 30, 2017		December 31, 2016
Domestic	113,078			71,382		61,706
Foreign	(4,456		)	4,984		(345		)
Income before income taxes	$	108,622		$	76,366	$	61,361

Components of income tax expense

The components of income tax expense were as follows (in thousands):



	Fiscal Year Ended
	December 29, 2018			December 30, 2017			December 31, 2016
Current
Federal	$	17,627		$	17,555		$	17,639
State	3,676			1,691			1,054
Foreign	10,732			7,355			310
Total current income tax provision	32,035			26,601			19,003
Deferred
Federal	$	(2,475	)	$	6,664		$	781
State	(1,149		)	(2,470		)	(95		)
Foreign	(7,781		)	(5,393		)	(267		)
Total deferred income tax provision	(11,405		)	(1,199		)	419
Total income tax provision	$	20,630		$	25,402		$	19,422

Reconciliation of the expected tax (benefit) expense

The reconciliation of statutory federal income tax to actual tax expense is as follows (in thousands):



	Fiscal Year Ended
	December 29, 2018			December 30, 2017			December 31, 2016
Statutory federal income tax	$	22,812		$	26,728		$	21,476
Miscellaneous permanent items	1,837			2,979			516
State taxes (net of federal benefit)	4,312			2,089			1,360
Federal and state credits	(5,638		)	(4,486		)	(2,233		)
Domestic production activities deduction	—			(1,528		)	(1,731		)
Excess tax benefits relating to stock-based compensation	(6,529		)	(11,709		)	—
Tax Cuts and Jobs Act of 2017	2,127			11,861			—
Foreign-derived intangible income deduction	(2,678		)	—			—
EMEA business restructuring	2,292			—			—
Other	2,095			(532		)	34
	$	20,630		$	25,402		$	19,422

Components of net deferred tax assets

The components of net deferred tax assets were as follows (in thousands):



	December 29, 2018			December 30, 2017
Deferred tax assets
Reserves and accruals	$	27,991		$	24,315
Tax credits and net operating loss carryforwards	7,781			6,810
Property and equipment	1,360			1,382
Stock-based compensation	4,975			4,277
Gross deferred tax assets	42,107			36,784
Valuation allowance	(1,148		)	(800		)
Total deferred tax assets	40,959			35,984
Deferred tax liabilities
Intangible assets	7,317			13,419
Other	668			573
Total deferred tax liabilities	7,985			13,992
Net deferred tax assets	$	32,974		$	21,992

Schedule of adjustments to uncertain tax position



	Fiscal Year Ended
	December 29, 2018			December 30, 2017			December 31, 2016
Balance at beginning of period	$	4,590		$	5,146		$	6,616
Increase for tax positions related to the current year	2,891			580			2,851
Increase for tax positions related to acquisition	1,493			—			—
Increase (decrease) for tax positions related to prior years	407			(523		)	(4,224		)
Decreases for settlements with applicable taxing authorities	(2,262		)	—			—
Decreases for lapses of statute of limitations	—			(613		)	(97		)
Balance at end of period	$	7,119		$	4,590		$	5,146

- Short Term Investments (Details) - USD ($) $ in Thousands	Dec. 29, 2018	Dec. 30, 2017
Components of available for sale securities
Total short term investments, Cost	$ 32,035	$ 37,767
Total short term investments, Fair Market Value	31,605	37,225
Corporate and government bonds
Components of available for sale securities
Total short term investments, Cost	30,035	37,767
Total short term investments, Fair Market Value	29,605	37,225
Convertible Debt [Member]
Components of available for sale securities
Total short term investments, Cost	2,000	0
Total short term investments, Fair Market Value	$ 2,000	$ 0

- Accounts Receivable Allowances (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 29, 2018	Dec. 30, 2017	Dec. 31, 2016
Allowance for other credits and incentives [Member]
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at beginning of period	$ 61,359	$ 23,658	$ 23,005
Acquired balance	0	11,932	0
Adjustment related to adoption of ASC 606	1,192	0	0
Provision	198,371	110,605	47,419
Deduction	(161,672)	(81,269)	(46,610)
Other adjustments	(1,513)	(3,567)	(156)
Balance at end of period	97,737	61,359	23,658
Allowance for product returns [Member]
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at beginning of period	42,693	27,673	25,992
Acquired balance	0	6,088	0
Provision	68,476	54,981	33,992
Deduction	(56,164)	(43,831)	(28,826)
Other adjustments	(1,085)	(2,218)	(3,485)
Balance at end of period	$ 53,920	$ 42,693	$ 27,673

- Property and Equipment (Details)	12 Months Ended
- Property and Equipment (Details)	Dec. 29, 2018
Leasehold improvements
Property, Plant and Equipment [Line Items]
Capital Leases and Leasehold Improvements Terms	Lesser of economic benefit period or term of lease
Furniture
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Useful Life	5 years
Minimum \| Computer and equipment
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Useful Life	2 years
Minimum \| Machinery
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Useful Life	2 years
Minimum \| Tooling
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Useful Life	2 years
Minimum \| Business applications software
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Useful Life	3 years
Maximum \| Computer and equipment
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Useful Life	5 years
Maximum \| Machinery
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Useful Life	5 years
Maximum \| Tooling
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Useful Life	5 years
Maximum \| Business applications software
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Useful Life	7 years

- Net Income Per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 29, 2018	Sep. 29, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 30, 2017	Sep. 30, 2017	Jul. 01, 2017	Apr. 01, 2017	Dec. 29, 2018	Dec. 30, 2017	Dec. 31, 2016
Basic and Diluted Net Income Per Share
Net income	$ 25,191	$ 31,929	$ 10,471	$ 20,401	$ 4,620	$ 22,082	$ 7,903	$ 16,359	$ 87,992	$ 50,964	$ 41,939
Weighted-average shares outstanding									27,692	27,611	27,698
Dilutive effect of employee stock options and restricted stock units									948	1,142	594
Diluted weighted-average shares outstanding									28,640	28,753	28,292
Basic									$ 3.18	$ 1.85	$ 1.51
Diluted	$ 0.88	$ 1.12	$ 0.37	$ 0.71	$ 0.16	$ 0.76	$ 0.27	$ 0.58	$ 3.07	$ 1.77	$ 1.48

- Definition

The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-04(19))
-URI http://asc.fasb.org/extlink&oid=114873790&loc=SL114874131-224263

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 45
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=109260490&loc=d3e1337-109256

Reference 3: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 55
-Paragraph 52
-URI http://asc.fasb.org/extlink&oid=109256448&loc=d3e4984-109258

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03(21))
-URI http://asc.fasb.org/extlink&oid=115205541&loc=SL114868664-224227

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 250
-SubTopic 10
-Section 50
-Paragraph 11
-URI http://asc.fasb.org/extlink&oid=109234566&loc=d3e22694-107794

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=109260490&loc=d3e1252-109256

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04(23))
-URI http://asc.fasb.org/extlink&oid=114873765&loc=SL114874048-224260

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 45
-Paragraph 60B
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=109260490&loc=SL5780133-109256

+ Details

- Definition

The amount of net income (loss) for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 55
-Paragraph 52
-URI http://asc.fasb.org/extlink&oid=109256448&loc=d3e4984-109258

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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+ Details

- Definition

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

+ References + Details

Summary of Significant Accounting Policies - Narrative (Details) - USD ($) $ in Thousands, shares in Millions	3 Months Ended	12 Months Ended
	Dec. 30, 2017	Dec. 29, 2018	Dec. 30, 2017	Dec. 31, 2016	Jan. 02, 2016
Accounting Policies [Line Items]
Equity Securities without Readily Determinable Fair Value, Amount	$ 14,200	$ 15,100	$ 14,200
Cash equivalents	128,600	130,400	128,600
Advertising Expense		114,000	91,800	$ 64,400
Valuation allowance	800	$ 1,148	$ 800	$ 0
Tax Cuts and Jobs Act of 2017, income tax expense (benefit), transition tax fior accumulated foreign earnings	3,000
Tax Cuts and Jobs Act of 2017, income tax expense (benefit)	11,900
Tax Cuts and Jobs Act of 2017, income tax expense (benefit), remeasurement of certain deferred tax assets and liabilities	8,900
Antidilutive securities excluded from computation of earnings per share (in shares)		0.0	0.0	0.4
Minimum
Accounting Policies [Line Items]
Warrant term		1 year
Maximum
Accounting Policies [Line Items]
Warrant term		2 years
Customer Concentration Risk \| Accounts Receivable \| Two Customers [Member]
Accounting Policies [Line Items]
Concentration risk percentage		23.10%
Customer Concentration Risk \| Accounts Receivable \| 1 Customer
Accounting Policies [Line Items]
Concentration risk percentage			11.50%
Customer Concentration Risk \| Revenue \| Amazon [Member]
Accounting Policies [Line Items]
Concentration risk percentage		17.30%	13.50%	10.40%
Customer Concentration Risk \| Revenue \| Sales On Demand Corporation (SODC)
Accounting Policies [Line Items]
Concentration risk percentage				12.90%
Customer Concentration Risk \| Revenue \| Robopolis
Accounting Policies [Line Items]
Concentration risk percentage				12.30%
Allowance for product returns
Accounting Policies [Line Items]
Valuation allowances and reserves	$ 42,693	$ 53,920	$ 42,693	$ 27,673	$ 25,992

Revenue Recognition Disaggregation of Revenue (Details) $ in Thousands	12 Months Ended
	Dec. 29, 2018 USD ($)
Americas [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	$ 610,294
EMEA [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	311,659
Asia Pacific [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	$ 170,631

Revenue Recognition Contract Balances (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 29, 2018	Dec. 31, 2017	Dec. 30, 2017
Revenue Recognition and Deferred Revenue [Abstract]
Contract with Customer, Liability, Revenue Recognized	$ 6,700
Accounts Receivable, Net, Current	162,166	$ 141,637	$ 142,829
Contract with Customer, Liability	$ 5,756	$ 6,685

Business Combinations - Robopolis Acquisition (Details) - USD ($) $ in Thousands		3 Months Ended		12 Months Ended
	Oct. 02, 2017	Dec. 29, 2018	Mar. 31, 2018	Dec. 29, 2018	Dec. 30, 2017	Dec. 31, 2016
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Net [Abstract]
Goodwill		$ 118,896		$ 118,896	$ 121,440	$ 41,041
Goodwill, Purchase Accounting Adjustments				$ 830
Robopolis
Business Acquisition [Line Items]
Payments to acquire business net of cash acquired	$ 170,100
Cash acquired from acquisition	38,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Net [Abstract]
Cash	37,981
Accounts receivable, net (1)	21,426
Inventory	36,304
Goodwill	80,419
Intangible assets	36,597
Other assets	2,456
Total assets	215,183
Accounts payable	(29,391)
Accrued expenses	(3,376)
Deferred tax liabilities	(10,864)
Other liabilities	(2,138)
Total liabilities assumed	45,769
Net assets acquired	169,414
Intangible assets acquired, fair value	$ 36,597
Goodwill, Purchase Accounting Adjustments		$ 1,500	$ 700
Reacquired distribution rights \| Robopolis
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Net [Abstract]
Intangible assets, useful life	2 years 3 months
Intangible assets acquired, fair value	$ 29,296
Customer relationships \| Robopolis
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Net [Abstract]
Intangible assets, useful life	14 years
Intangible assets acquired, fair value	$ 7,029
Non-competition agreements \| Robopolis
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Net [Abstract]
Intangible assets, useful life	3 years
Intangible assets acquired, fair value	$ 272

Business Combinations - Sales On Demand Corporation Acquisition (Details) - USD ($) $ in Thousands			12 Months Ended
	Oct. 02, 2017	Apr. 03, 2017	Dec. 29, 2018	Dec. 30, 2017	Dec. 31, 2016
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Net [Abstract]
Goodwill			$ 118,896	$ 121,440	$ 41,041
Gain on business acquisition			$ 0	(2,243)	$ 0
Sales On Demand Corporation
Business Acquisition [Line Items]
Payments to Acquire Businesses, Gross				16,649
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Net [Abstract]
Cash		$ 125
Accounts receivable, net (1)		(5,496)
Inventory		18,290
Deferred tax assets, net		409
Goodwill		0
Intangible assets		8,640
Total assets		24,033
Accrued expenses and other current liabilities		(4,450)
Other liabilities		(691)
Total liabilities assumed		(5,141)
Net assets acquired		18,892
Gain on business acquisition				$ (2,243)
Intangible assets acquired, fair value		8,640
Other assets		$ 2,065
Sales On Demand Corporation \| Customer relationships
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Net [Abstract]
Intangible assets, useful life		13 years
Intangible assets acquired, fair value		$ 4,490
Sales On Demand Corporation \| Reacquired distribution rights
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Net [Abstract]
Intangible assets, useful life		9 months
Intangible assets acquired, fair value		$ 4,150
Robopolis
Business Acquisition [Line Items]
Payments to Acquire Businesses, Gross	$ 170,100
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Net [Abstract]
Cash	37,981
Accounts receivable, net (1)	21,426
Inventory	36,304
Goodwill	80,419
Intangible assets	36,597
Total assets	215,183
Other liabilities	(2,138)
Total liabilities assumed	(45,769)
Net assets acquired	169,414
Intangible assets acquired, fair value	36,597
Other assets	$ 2,456
Robopolis \| Customer relationships
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Net [Abstract]
Intangible assets, useful life	14 years
Intangible assets acquired, fair value	$ 7,029
Robopolis \| Reacquired distribution rights
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Net [Abstract]
Intangible assets, useful life	2 years 3 months
Intangible assets acquired, fair value	$ 29,296

Business Combinations - Pro Forma (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 29, 2018	Sep. 29, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 30, 2017	Sep. 30, 2017	Jul. 01, 2017	Apr. 01, 2017	Dec. 29, 2018	Dec. 30, 2017	Dec. 31, 2016
Business Combinations [Abstract]
Revenue	$ 384,665	$ 264,534	$ 226,317	$ 217,068	$ 326,897	$ 205,399	$ 183,148	$ 168,467	$ 1,092,584	$ 883,911	$ 660,604
Revenue										901,612	718,917
Net income	$ 25,191	$ 31,929	$ 10,471	$ 20,401	$ 4,620	$ 22,082	$ 7,903	$ 16,359	$ 87,992	50,964	41,939
Net income										$ 51,887	$ 53,320
Basic									$ 3.18	$ 1.85	$ 1.51
Basic income per share (in dollars per share)										1.88	1.93
Diluted	$ 0.88	$ 1.12	$ 0.37	$ 0.71	$ 0.16	$ 0.76	$ 0.27	$ 0.58	$ 3.07	1.77	1.48
Diluted income per share (in dollars per share)										$ 1.80	$ 1.88

- Definition

The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period.

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

+ References + Details

Inventory (Details) - USD ($) $ in Thousands	Dec. 29, 2018	Dec. 30, 2017
Inventory
Raw materials	$ 2,992	$ 4,036
Finished goods	161,641	102,896
Total	$ 164,633	$ 106,932

Property and Equipment 1 (Details) - USD ($) $ in Thousands	12 Months Ended
Property and Equipment 1 (Details) - USD ($) $ in Thousands	Dec. 29, 2018	Dec. 30, 2017	Dec. 31, 2016
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	$ 122,190	$ 99,667
Less: accumulated depreciation	65,164	55,088
Property, Plant and Equipment, Net	57,026	44,579
Capitalized Computer Software, Net	4,700	2,800
Depreciation	17,000	12,300	$ 10,000
Capitalized Computer Software, Amortization	1,200	1,500	$ 400
Computer and equipment
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	12,339	10,669
Furniture
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	5,231	4,120
Machinery
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	20,606	14,202
Tooling
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	39,675	31,783
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	28,701	26,136
Business applications software
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	$ 15,638	$ 12,757

Goodwill and other intangible assets - Goodwill (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 29, 2018	Dec. 30, 2017
Goodwill [Roll Forward]
Goodwill	$ 121,440	$ 41,041
Acquisitions (Note 4)		79,558
Purchase accounting adjustments (Note 4)	830
Effect of foreign currency translation	(3,374)	841
Goodwill	$ 118,896	$ 121,440

Goodwill and other intangible assets - Intangible Assets (Details) - USD ($) $ in Thousands	Dec. 29, 2018	Dec. 30, 2017
Finite-Lived Intangible Assets, Net [Abstract]
Cost	$ 71,053	$ 72,629
Accumulated Amortization	46,780	27,917
Net	24,273	44,712
Completed technology
Finite-Lived Intangible Assets, Net [Abstract]
Cost	26,900	26,900
Accumulated Amortization	21,607	18,150
Net	5,293	8,750
Tradename
Finite-Lived Intangible Assets, Net [Abstract]
Cost	100	100
Accumulated Amortization	100	100
Net	0	0
Customer relationships
Finite-Lived Intangible Assets, Net [Abstract]
Cost	11,291	11,594
Accumulated Amortization	1,365	418
Net	9,926	11,176
Reacquired distribution rights
Finite-Lived Intangible Assets, Net [Abstract]
Cost	32,499	33,760
Accumulated Amortization	23,598	9,226
Net	8,901	24,534
Non-competition agreements
Finite-Lived Intangible Assets, Net [Abstract]
Cost	263	275
Accumulated Amortization	110	23
Net	$ 153	$ 252

Goodwill and other intangible assets - Future Amortization Expense (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 29, 2018	Dec. 30, 2017	Dec. 31, 2016
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Amortization Expense, Next Twelve Months	$ 12,761
Finite-Lived Intangible Assets, Amortization Expense, Year Two	1,920
Finite-Lived Intangible Assets, Amortization Expense, Year Three	1,694
Finite-Lived Intangible Assets, Amortization Expense, Year Four	1,469
Finite-Lived Intangible Assets, Amortization Expense, Year Five	794
Finite-Lived Intangible Assets, Amortization Expense, after Year Five	5,635
Finite-lived intangible assets, future amortization total	24,273
Amortization of intangible assets	19,600	$ 13,100	$ 3,500
Cost of revenue
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Amortization Expense, Next Twelve Months	11,719
Finite-Lived Intangible Assets, Amortization Expense, Year Two	900
Finite-Lived Intangible Assets, Amortization Expense, Year Three	900
Finite-Lived Intangible Assets, Amortization Expense, Year Four	675
Finite-Lived Intangible Assets, Amortization Expense, Year Five	0
Finite-Lived Intangible Assets, Amortization Expense, after Year Five	0
Finite-lived intangible assets, future amortization total	14,194
Operating Expense [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Amortization Expense, Next Twelve Months	1,042
Finite-Lived Intangible Assets, Amortization Expense, Year Two	1,020
Finite-Lived Intangible Assets, Amortization Expense, Year Three	794
Finite-Lived Intangible Assets, Amortization Expense, Year Four	794
Finite-Lived Intangible Assets, Amortization Expense, Year Five	794
Finite-Lived Intangible Assets, Amortization Expense, after Year Five	5,635
Finite-lived intangible assets, future amortization total	$ 10,079

Accrued Expenses (Details) - USD ($) $ in Thousands	Dec. 29, 2018	Dec. 30, 2017
Components of accrued expenses
Accrued bonus	$ 21,226	$ 20,443
Accrued warranty	11,964	11,264
Accrued other compensation	10,518	9,071
Accrued sales and other taxes	11,397	7,256
Accrued federal and state income taxes	1,936	7,110
Accrued direct fulfillment costs	5,372	1,885
Accrued accounting fees	2,052	1,221
Accrued other	6,794	15,397
Accrued expenses, total	$ 71,259	$ 73,647

Working Capital Facilities (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 29, 2018	Dec. 30, 2017
Revolving Line of Credit (Textual) [Abstract]
Maximum amount available for borrowing under credit facility	$ 150,000	$ 75,000
Interest on loans under the credit facility	at either (1) LIBOR plus a margin, currently equal to 1.0%, based on the Company's ratio of indebtedness to Adjusted EBITDA (the "Eurodollar Rate"), or (2) the lender's base rate.
Interest rate above the LIBOR Daily Floating Rate or the Prime Rate of Lender under condition one	1.00%
Interest Rate Above the Federal Fund Rate Under Condition Two	0.50%
Interest rate above the LIBOR rate plus under condition two	1.00%
Line of Credit Facility, Amount Outstanding	$ 0

- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

+ References + Details

Derivative Instruments and Hedging Activities - Fair Value of Derivatives (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 29, 2018	Dec. 30, 2017
Derivatives not designated as hedging instruments:
Derivatives, Fair Value [Line Items]
Derivative notional amount	$ 56,000	$ 36,600
Foreign currency forward contracts \| Derivatives not designated as hedging instruments: \| Other current assets
Derivative, Fair Value, Net [Abstract]
Derivative Asset	551	413
Foreign currency forward contracts \| Derivatives not designated as hedging instruments: \| Accrued expenses
Derivative, Fair Value, Net [Abstract]
Derivative Liability	0	221
Cash flow hedge \| Derivatives designated as cash flow hedges:
Derivatives, Fair Value [Line Items]
Derivative notional amount	366,700	73,700
Cash flow hedge \| Foreign currency forward contracts \| Derivatives designated as cash flow hedges: \| Other current assets
Derivative, Fair Value, Net [Abstract]
Derivative Asset	53	488
Cash flow hedge \| Foreign currency forward contracts \| Derivatives designated as cash flow hedges: \| Other assets
Derivative, Fair Value, Net [Abstract]
Derivative Asset	172	116
Cash flow hedge \| Foreign currency forward contracts \| Derivatives designated as cash flow hedges: \| Accrued expenses
Derivative, Fair Value, Net [Abstract]
Derivative Liability	335	279
Cash flow hedge \| Foreign currency forward contracts \| Derivatives designated as cash flow hedges: \| Other Noncurrent Liabilities [Member]
Derivative, Fair Value, Net [Abstract]
Derivative Liability	$ 795	$ 0
Maximum \| Derivatives not designated as hedging instruments:
Derivatives, Fair Value [Line Items]
Derivative term	2 months
Maximum \| Cash flow hedge \| Derivatives designated as cash flow hedges:
Derivatives, Fair Value [Line Items]
Derivative term	37 months

Derivative Instruments and Hedging Activities - Gain (Loss) on Derivatives (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 29, 2018	Dec. 30, 2017
Other income, net
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) recognized in income	$ 1,568	$ (444)
Foreign currency forward contracts \| Cash flow hedge
Derivative Instruments, Gain (Loss) [Line Items]
Effective portion, Gain (loss) recognized in OCI on Derivative	(686)	584
Foreign currency forward contracts \| Revenue \| Cash flow hedge
Derivative Instruments, Gain (Loss) [Line Items]
Effective portion, Gain (loss) reclassified from accumulated OCI into income	948	320
Foreign currency forward contracts \| Cost of revenue \| Cash flow hedge
Derivative Instruments, Gain (Loss) [Line Items]
Effective portion, Gain (loss) reclassified from accumulated OCI into income	$ (386)	$ (63)

Fair Value Measurements (Details) - USD ($) $ in Thousands	Dec. 29, 2018	Dec. 30, 2017
Assets:
Convertible note	$ 2,000	$ 0
Recurring \| Level 1
Assets:
Corporate and government bonds, $30,035 at cost (3)	0	0
Derivative instruments (Note 10)	0	0
Total assets measured at fair value	3,730	3,165
Liabilities:
Derivative instruments (Note 10)	0	0
Total liabilities measured at fair value	0	0
Recurring \| Level 1 \| Money market funds
Assets:
Money market funds	3,730	3,165
Recurring \| Level 2
Assets:
Corporate and government bonds, $30,035 at cost (3)	29,605	37,225
Convertible note	0
Derivative instruments (Note 10)	776	1,017
Total assets measured at fair value	30,381	38,242
Liabilities:
Derivative instruments (Note 10)	1,130	500
Total liabilities measured at fair value	1,130	500
Recurring \| Level 2 \| Money market funds
Assets:
Money market funds	0	0
Recurring \| Level 3 (2)
Assets:
Corporate and government bonds, $30,035 at cost (3)	0	0
Convertible note	2,000
Derivative instruments (Note 10)	0	0
Total assets measured at fair value	2,000	0
Liabilities:
Derivative instruments (Note 10)	0	0
Total liabilities measured at fair value	0	0
Recurring \| Level 3 (2) \| Money market funds
Assets:
Money market funds	$ 0	$ 0

Stockholders' Equity (Details)	12 Months Ended
Stockholders' Equity (Details)	Dec. 29, 2018 USD ($) vote $ / shares shares	Dec. 31, 2016 USD ($) shares	Feb. 27, 2018 USD ($)	Dec. 30, 2017 $ / shares shares	Mar. 01, 2016 USD ($)	Dec. 28, 2015 USD ($) shares
Equity [Abstract]
Preferred stock, shares authorized	5,000,000			5,000,000
Preferred stock, par value (in dollars per share) \| $ / shares	$ 0.01			$ 0.01
Preferred stock, shares issued	0			0
Preferred stock, shares outstanding	0			0
Common stock, votes per share \| vote	1
Stock repurchase program, authorized amount \| $			$ 50,000,000		$ 85,000,000	$ 40,000,000
Stock repurchase program, authorized amount (in shares)						1,000,000
Stock repurchases (in shares)	798,794	2,641,122
Stock repurchases \| $	$ 50,000,000	$ 97,021,000

Stock-Based Compensation - Narrative (Details) $ in Millions	12 Months Ended
	Dec. 29, 2018 USD ($) plan shares	Dec. 30, 2017 USD ($)	Dec. 31, 2016 USD ($)	May 23, 2018 shares
Number of plans \| plan	4
Capital shares reserved for future issuance				1,750,000
Number of shares available for grant	1,623,670
Share-based compensation expense \| $	$ 25.8	$ 19.8	$ 16.0

Stock-Based Compensation - Stock Options Activity (Details) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 29, 2018	Dec. 30, 2017	Dec. 31, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation not yet recognized, options	$ 1.8
Summary of stock option plan activity
Number of Shares, Beginning Balance	712,954	1,088,174	1,287,550
Number of Shares, Granted	0	10,975	314,770
Number of Shares, Exercised	(239,830)	(367,267)	(456,498)
Number of Shares, Canceled	(10,863)	(18,928)	(57,648)
Number of Shares, Ending Balance	462,261	712,954	1,088,174
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Abstract]
Weighted Average Exercise Price, Beginning Balance (in dollars per share)	$ 34.34	$ 32.27	$ 26.73
Weighted Average Exercise Price, Granted (in dollars per share)	0.00	57.33	38.03
Weighted Average Exercise Price, Exercised (in dollars per share)	33.40	28.79	20.47
Weighted Average Exercise Price, Canceled (in dollars per share)	46.20	36.72	33.28
Weighted Average Exercise Price, Ending Balance (in dollars per share)	$ 34.55	$ 34.34	$ 32.27
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract]
Number of Shares, Vested and expected to vest	462,261
Number of Shares, Exercisable	317,997
Weighted Average Exercise Price, Vested and expected to vest (in dollars per share)	$ 34.55
Weighted Average Exercise Price, Exercisable (in dollars per share)	$ 33.10
Weighted Average Remaining Contractual Term, Vested and expected to vest	3 years 6 months 29 days
Weighted Average Remaining Contractual Term, Ending Balance	3 years 6 months 29 days
Weighted Average Remaining Contractual Term, Exercisable	3 years 3 months 4 days
Aggregate Intrinsic Value, Ending Balance	$ 21.6
Aggregate Intrinsic Value, Vested and expected to vest	21.6
Aggregate Intrinsic Value, Exercisable	$ 15.3
Share price (in dollars per share)	$ 81.32
Employee Stock Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period	4 years
Weighted average remaining recognition period	1 year 3 months 15 days
Employee Stock Option \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Minimum expiration period for options	5 years
Employee Stock Option \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Minimum expiration period for options	10 years

Stock-Based Compensation - Stock Options Assumptions (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 29, 2018	Dec. 30, 2017	Dec. 31, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options, exercises in period, intrinsic value	$ 14.9	$ 21.8	$ 10.3
Fair value of each option grant computed on the grant date
Risk-free interest rate, minimum	0.00%	2.11%	1.17%
Risk-free interest rate, maximum	0.00%	2.11%	1.89%
Expected volatility, minimum	0.00%	38.00%	38.90%
Expected volatility, maximum	0.00%	38.00%	42.10%
Minimum
Fair value of each option grant computed on the grant date
Expected dividend rate	0.00%	0.00%	0.00%
Expected life	0 days	4 years 5 days	4 years 5 days
Maximum
Fair value of each option grant computed on the grant date
Expected dividend rate	0.00%	0.00%	0.00%
Expected life	0 days	4 years 5 days	4 years 11 days

Stock-Based Compensation - Stock Options Exercise Price Range (Details)	12 Months Ended
	Dec. 29, 2018 $ / shares shares
Share Based Compensation Shares Authorized Under Stock Option Plans Exercise Price Range [Line Items]
Range of Exercise Price, Minimum	$ 3.54
Range of Exercise Price, Maximum	$ 58.55
Number Outstanding \| shares	462,261
Options Outstanding Weighted Average Remaining Contractual Life	3 years 6 months 29 days
Weighted Average Exercise Price	$ 34.55
Number Exercisable \| shares	317,997
Weighted Average Exercise Price	$ 33.10
$ 3.54 - $ 22.86
Share Based Compensation Shares Authorized Under Stock Option Plans Exercise Price Range [Line Items]
Range of Exercise Price, Minimum	3.54
Range of Exercise Price, Maximum	$ 22.86
Number Outstanding \| shares	46,918
Options Outstanding Weighted Average Remaining Contractual Life	1 year 6 months 18 days
Weighted Average Exercise Price	$ 19.84
Number Exercisable \| shares	46,918
Weighted Average Exercise Price	$ 19.84
26.59 - 32.38
Share Based Compensation Shares Authorized Under Stock Option Plans Exercise Price Range [Line Items]
Range of Exercise Price, Minimum	26.59
Range of Exercise Price, Maximum	$ 32.38
Number Outstanding \| shares	83,084
Options Outstanding Weighted Average Remaining Contractual Life	3 years 6 months 4 days
Weighted Average Exercise Price	$ 30.98
Number Exercisable \| shares	62,968
Weighted Average Exercise Price	$ 31.05
33.14 - 33.14
Share Based Compensation Shares Authorized Under Stock Option Plans Exercise Price Range [Line Items]
Range of Exercise Price, Minimum	33.14
Range of Exercise Price, Maximum	$ 33.14
Number Outstanding \| shares	85,984
Options Outstanding Weighted Average Remaining Contractual Life	4 years 2 months 9 days
Weighted Average Exercise Price	$ 33.14
Number Exercisable \| shares	48,436
Weighted Average Exercise Price	$ 33.14
33.29 - 34.30
Share Based Compensation Shares Authorized Under Stock Option Plans Exercise Price Range [Line Items]
Range of Exercise Price, Minimum	33.29
Range of Exercise Price, Maximum	$ 34.30
Number Outstanding \| shares	71,864
Options Outstanding Weighted Average Remaining Contractual Life	3 years 3 months 4 days
Weighted Average Exercise Price	$ 34.07
Number Exercisable \| shares	57,664
Weighted Average Exercise Price	$ 34.07
35.43 - 37.08
Share Based Compensation Shares Authorized Under Stock Option Plans Exercise Price Range [Line Items]
Range of Exercise Price, Minimum	35.43
Range of Exercise Price, Maximum	$ 37.08
Number Outstanding \| shares	28,276
Options Outstanding Weighted Average Remaining Contractual Life	2 years 6 months 7 days
Weighted Average Exercise Price	$ 35.69
Number Exercisable \| shares	28,276
Weighted Average Exercise Price	$ 35.69
37.62 - 37.62
Share Based Compensation Shares Authorized Under Stock Option Plans Exercise Price Range [Line Items]
Range of Exercise Price, Minimum	37.62
Range of Exercise Price, Maximum	$ 37.62
Number Outstanding \| shares	78,419
Options Outstanding Weighted Average Remaining Contractual Life	4 years 5 months 9 days
Weighted Average Exercise Price	$ 37.62
Number Exercisable \| shares	38,874
Weighted Average Exercise Price	$ 37.62
39.09 - 39.09
Share Based Compensation Shares Authorized Under Stock Option Plans Exercise Price Range [Line Items]
Range of Exercise Price, Minimum	39.09
Range of Exercise Price, Maximum	$ 39.09
Number Outstanding \| shares	23,367
Options Outstanding Weighted Average Remaining Contractual Life	4 years 8 months 12 days
Weighted Average Exercise Price	$ 39.09
Number Exercisable \| shares	7,566
Weighted Average Exercise Price	$ 39.09
43.35 - 43.35
Share Based Compensation Shares Authorized Under Stock Option Plans Exercise Price Range [Line Items]
Range of Exercise Price, Minimum	43.35
Range of Exercise Price, Maximum	$ 43.35
Number Outstanding \| shares	19,194
Options Outstanding Weighted Average Remaining Contractual Life	2 years 2 months 9 days
Weighted Average Exercise Price	$ 43.35
Number Exercisable \| shares	19,194
Weighted Average Exercise Price	$ 43.35
57.33 - 57.33
Share Based Compensation Shares Authorized Under Stock Option Plans Exercise Price Range [Line Items]
Range of Exercise Price, Minimum	57.33
Range of Exercise Price, Maximum	$ 57.33
Number Outstanding \| shares	8,046
Options Outstanding Weighted Average Remaining Contractual Life	5 years 2 months 9 days
Weighted Average Exercise Price	$ 57.33
Number Exercisable \| shares	2,985
Weighted Average Exercise Price	$ 57.33
58.55 - 58.55
Share Based Compensation Shares Authorized Under Stock Option Plans Exercise Price Range [Line Items]
Range of Exercise Price, Minimum	58.55
Range of Exercise Price, Maximum	$ 58.55
Number Outstanding \| shares	17,109
Options Outstanding Weighted Average Remaining Contractual Life	4 years 11 months 12 days
Weighted Average Exercise Price	$ 58.55
Number Exercisable \| shares	5,116
Weighted Average Exercise Price	$ 58.55

Stock-Based Compensation - RSUs and PSUs (Details) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 29, 2018	Dec. 30, 2017	Dec. 31, 2016
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Share price (in dollars per share)	$ 81.32
Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period	4 years
Compensation cost not yet recognized	$ 44.0
Weighted average remaining recognition period	2 years 3 months 29 days
Activities relating to restricted stock awards
Number of Shares Underlying Restricted Stock, Beginning Balance	938,453	935,179	933,877
Number of Shares Underlying Restricted Stock, Granted	307,614	396,164	458,237
Number of Shares Underlying Restricted Stock, Vested	(351,816)	(351,543)	(358,018)
Number of Shares Underlying Restricted Stock, Forfeited	(38,362)	(41,347)	(98,917)
Number of Shares Underlying Restricted Stock, Ending Balance	855,889	938,453	935,179
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Weighted Average Grant Date Fair Value, Beginning Balance (in dollars per share)	$ 51.24	$ 35.07	$ 31.42
Weighted Average Grant Date Fair Value, Granted (in dollars per share)	81.55	72.63	37.93
Weighted Average Grant Date Fair Value, Vested (in dollars per share)	47.30	33.73	30.81
Weighted Average Grant Date Fair Value, Forfeited (in dollars per share)	60.62	39.52	32.13
Weighted Average Grant Date Fair Value, Ending Balance (in dollars per share)	$ 63.32	$ 51.24	$ 35.07
Outstanding, aggregate intrinsic value	$ 69.6
Outstanding, weighted average remaining contractual term	1 year 4 months 24 days
Performance Based Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period	3 years
Compensation cost not yet recognized	$ 7.1
Weighted average remaining recognition period	1 year 2 months 27 days
Activities relating to restricted stock awards
Number of Shares Underlying Restricted Stock, Beginning Balance	242,061	163,911	90,492
Number of Shares Underlying Restricted Stock, Granted	91,538	105,650	82,085
Number of Shares Underlying Restricted Stock, Vested	(56,259)	(24,792)	(5,625)
Number of Shares Underlying Restricted Stock, Forfeited	(3,221)	(2,708)	(3,041)
Number of Shares Underlying Restricted Stock, Ending Balance	274,119	242,061	163,911
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Weighted Average Grant Date Fair Value, Beginning Balance (in dollars per share)	$ 43.97	$ 35.03	$ 36.78
Weighted Average Grant Date Fair Value, Granted (in dollars per share)	68.41	57.33	33.36
Weighted Average Grant Date Fair Value, Vested (in dollars per share)	34.30	43.35	34.30
Weighted Average Grant Date Fair Value, Forfeited (in dollars per share)	45.71	39.71	34.30
Weighted Average Grant Date Fair Value, Ending Balance (in dollars per share)	$ 54.10	$ 43.97	$ 35.03
Outstanding, aggregate intrinsic value	$ 22.3
Outstanding, weighted average remaining contractual term	1 year 2 months 27 days
Performance Based Restricted Stock Units \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting rights percentage	0.00%
Performance Based Restricted Stock Units \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting rights percentage	200.00%

Stock-Based Compensation - ESPP (Details) - USD ($)	1 Months Ended	12 Months Ended
Stock-Based Compensation - ESPP (Details) - USD ($)	May 31, 2017	Dec. 29, 2018	Dec. 30, 2017	May 23, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Capital shares reserved for future issuance				1,750,000
Maximum percentage of salary	15.00%
Maximum dollar amount	$ 4,000
Maximum number of shares per employee	1,000
Number of shares available for grant		1,623,670
Purchase price of common stock percent	85.00%
Employee Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares available for grant		631,542
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost		$ 1,000,000	$ 100,000

Commitments and Contingencies (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 29, 2018	Dec. 30, 2017	Dec. 31, 2016
Commitments and Contingencies Disclosure [Abstract]
Rental expense under operating leases	$ 12,900	$ 8,900	$ 6,000
Summary of future minimum rental payments under operating leases
2018	7,848
2019	7,397
2020	7,345
2021	7,292
2022	7,021
Thereafter	34,806
Total minimum lease payments	71,709
Contractual Obligation	$ 113,600

Commitments and Contingencies (Details 1) - USD ($) $ in Thousands	12 Months Ended
	Dec. 29, 2018	Dec. 30, 2017	Dec. 31, 2016
Activity related to the warranty accrual
Balance at beginning of period	$ 11,264	$ 8,464	$ 6,907
Liability assumed	0	2,186	0
Provision	10,798	8,591	7,494
Warranty usage	(10,098)	(7,977)	(5,937)
Balance at end of period	$ 11,964	$ 11,264	$ 8,464

Employee Benefits (Details) - USD ($) $ in Millions	12 Months Ended
Employee Benefits (Details) - USD ($) $ in Millions	Dec. 29, 2018	Dec. 30, 2017	Dec. 31, 2016
Retirement Benefits [Abstract]
Defined Contribution Plan, Cost	$ 2.8	$ 2.4	$ 1.7
Defined Contribution Plan, Employer Matching Contribution, Percent of Match	50.00%
Defined Contribution Plan, Employer Matching Contribution, Percent of Employees' Gross Pay	6.00%
Defined Contribution Plan, Maximum Annual Contributions Per Employee, Percent	3.00%

Income Taxes - Income (Loss) Before Provision For Income Taxes (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 29, 2018	Dec. 30, 2017	Dec. 31, 2016
Income Tax Disclosure [Abstract]
Domestic	$ 113,078	$ 71,382	$ 61,706
Foreign	(4,456)	4,984	(345)
Income before income taxes	$ 108,622	$ 76,366	$ 61,361

Income Taxes - Components of Income Tax Expense (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 29, 2018	Dec. 30, 2017	Dec. 31, 2016
Current
Federal	$ 17,627	$ 17,555	$ 17,639
State	3,676	1,691	1,054
Foreign	10,732	7,355	310
Total current income tax provision	32,035	26,601	19,003
Deferred
Federal	(2,475)	6,664	781
State	(1,149)	(2,470)	(95)
Foreign	(7,781)	(5,393)	(267)
Total deferred income tax provision	(11,405)	(1,199)	419
Total income tax provision	$ 20,630	$ 25,402	$ 19,422

Income Taxes - Effective Income Tax Reconciliation (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 29, 2018	Dec. 30, 2017	Dec. 31, 2016
Reconciliation of the expected tax (benefit) expense
Expected federal income tax	$ 22,812	$ 26,728	$ 21,476
Miscellaneous permanent items	1,837	2,979	516
State taxes (net of federal benefit)	4,312	2,089	1,360
Federal and state credits	(5,638)	(4,486)	(2,233)
Domestic production activities deduction	0	(1,528)	(1,731)
Excess tax benefits relating to stock-based compensation	(6,529)	(11,709)	0
Tax Cuts and Jobs Act of 2017	2,127	11,861	0
Effective Income Tax Rate Reconciliation, Foreign derived intangible income deduction	(2,678)	0	0
Effective Income Tax Rate Reconciliation, EMEA business restructuring	2,292	0	0
Unrecognized Tax Benefits, Decrease Resulting from Prior Period Tax Positions		(523)	(4,224)
Other	2,095	(532)	34
Total expected tax (benefits) expenses	$ 20,630	$ 25,402	$ 19,422

Income Taxes - Net Deferred Tax Assets (Details) - USD ($) $ in Thousands	Dec. 29, 2018	Dec. 30, 2017	Dec. 31, 2016
Deferred tax assets
Reserves and accruals	$ 27,991	$ 24,315
Tax credits and net operating loss carryforwards	7,781	6,810
Property and equipment	1,360	1,382
Stock-based compensation	4,975	4,277
Deferred Tax Assets, Gross	42,107	36,784
Valuation allowance	(1,148)	(800)	$ 0
Total deferred tax assets	40,959	35,984
Deferred tax liabilities
Intangible assets	7,317	13,419
Other	668	573
Reserves and accruals	7,985	13,992
Deferred Tax Assets, Net	$ 32,974	$ 21,992

Income Taxes - Unrecognized Tax Benefits (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 29, 2018	Dec. 30, 2017	Dec. 31, 2016
Company's adjustments to its uncertain tax position
Balance at beginning of period	$ 4,590	$ 5,146	$ 6,616
Increase for tax positions related to the current year	2,891	580	2,851
Unrecognized Tax Benefits, Increase Resulting from Acquisition	1,493	0	0
Decrease for tax positions related to prior years		(523)	(4,224)
Increase for tax positions related to prior years	407
Decreases for settlements with applicable taxing authorities	(2,262)	0	0
Decreases for lapses of statute of limitations	0	(613)	(97)
Balance at end of period	$ 7,119	$ 4,590	$ 5,146

Income Taxes - Narrative (Details) - USD ($)	3 Months Ended
Income Taxes - Narrative (Details) - USD ($)	Dec. 30, 2017	Dec. 29, 2018	Dec. 31, 2016
Tax Credit Carryforward [Line Items]
Tax Cuts and Jobs Act of 2017, income tax expense (benefit)	$ 11,900,000
Tax Cuts and Jobs Act of 2017, income tax expense (benefit), remeasurement of certain deferred tax assets and liabilities	8,900,000
Tax Cuts and Jobs Act of 2017, income tax expense (benefit), transition tax fior accumulated foreign earnings	3,000,000
Operating loss carryforwards	100,000	$ 3,400,000
Valuation allowance	800,000	1,148,000	$ 0
Income tax penalties and interest accrued	0	0	$ 0
Unrecognized tax benefits that would impact effective tax rate		7,400,000
State and Local Jurisdiction
Tax Credit Carryforward [Line Items]
Tax credit carryforward	$ 10,100,000	$ 10,700,000

Industry Segment, Geographic Information and Significant Customers (Details Textual)	12 Months Ended
	Dec. 29, 2018	Dec. 30, 2017	Dec. 31, 2016
Geographic Concentration Risk \| Revenue \| Foreign
Revenues from External Customers and Long-Lived Assets [Line Items]
Concentration risk percentage	48.70%	48.80%	51.20%

Quarterly Information (Unaudited) (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 29, 2018	Sep. 29, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 30, 2017	Sep. 30, 2017	Jul. 01, 2017	Apr. 01, 2017	Dec. 29, 2018	Dec. 30, 2017	Dec. 31, 2016
Quarterly Financial Information Disclosure [Abstract]
Revenue	$ 384,665	$ 264,534	$ 226,317	$ 217,068	$ 326,897	$ 205,399	$ 183,148	$ 168,467	$ 1,092,584	$ 883,911	$ 660,604
Details of Quarterly Information (Unaudited)
Gross profit	186,511	135,206	117,926	115,785	153,542	102,383	89,891	87,343	555,428	433,159	319,315
Net income	$ 25,191	$ 31,929	$ 10,471	$ 20,401	$ 4,620	$ 22,082	$ 7,903	$ 16,359	$ 87,992	$ 50,964	$ 41,939
Diluted	$ 0.88	$ 1.12	$ 0.37	$ 0.71	$ 0.16	$ 0.76	$ 0.27	$ 0.58	$ 3.07	$ 1.77	$ 1.48

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

+ References + Details

Summary of Significant Accounting Policies Other assets (Details) - USD ($) $ in Millions	Dec. 29, 2018	Dec. 30, 2017
Investments, Debt and Equity Securities [Abstract]
Equity Securities without Readily Determinable Fair Value, Amount	$ 15.1	$ 14.2

Revenue Recognition Significant Judgments (Details) - USD ($) $ in Millions	Dec. 29, 2018	Dec. 30, 2017
Revenue Recognition and Deferred Revenue [Abstract]
Refund liability, product returns	$ 53.9	$ 42.7
Refund liability, other credits and incentives	$ 97.7	$ 61.4

Summary of Significant Accounting Policies Income taxes (Details) - USD ($) $ in Thousands	Dec. 29, 2018	Dec. 30, 2017	Dec. 31, 2016
Income taxes [Abstract]
Valuation allowance	$ 1,148	$ 800	$ 0

Revenue Recognition Initial application (Details) - USD ($) $ in Thousands	Dec. 29, 2018	Dec. 30, 2017
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Cumulative Effect of New Accounting Principle in Period of Adoption	$ 1,040	$ 858

Useful Life

Fair Value

Customer relationships

Reacquired distribution rights