Income Taxes - Income Tax Rate Reconciliation (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 29, 2018	Dec. 30, 2017	Dec. 31, 2016
Income Tax Expense Benefit Continuing Operations Income Tax Reconciliation [Abstract]
Income taxes computed at U.S. statutory rate	$ 14,180	$ 15,153	$ 10,197
State income taxes	379	227	223
Foreign tax rate differential	(2,382)	794	3,502
Change in valuation allowance	3,037	1,490	(25,738)
Non-deductible equity compensation	(1,241)	(1,803)	380
Tax credits	(3,876)	(2,336)	(3,191)
Domestic production activities deduction		(608)	(354)
Liabilities for uncertain tax positions	12	18	67
Other, net	(233)	161	14
Provision (benefit) for income taxes	$ 9,876	$ 13,096	$ (14,900)

Income tax reconciliation, liabilities for uncertain tax positions.

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Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to increase (decrease) in the valuation allowance for deferred tax assets.

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Amount of the difference between reported income tax expense (benefit) and the expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to deduction for qualified production activity.

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Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to tax credits. Including, but not limited to, research credit, foreign tax credit, investment tax credit, and other tax credits.

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