Accumulated Other Comprehensive Income (Loss) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 28, 2019	Dec. 29, 2018	Dec. 30, 2017
AOCI Attributable to Parent, Net of Tax:
Beginning balance, tax	$ (964)	$ (879)	$ (879)
Beginning balance	703,821	665,365	762,328
Other comprehensive income (loss) before reclassifications, tax	0	(85)	0
Other comprehensive income (loss) before reclassifications, net of tax	(10,977)	(31,788)	34,578
Amounts reclassified from accumulated other comprehensive income (loss), tax	0	0	0
Amounts reclassified from accumulated other comprehensive income (loss), net of tax	1,638	234	0
Net current-period other comprehensive income (loss), tax	0	(85)	0
Net change in accumulated other comprehensive income (loss)	(9,339)	(31,554)	34,578
Ending balance, tax	(964)	(964)	(879)
End of period	386,535	703,821	665,365
Accumulated Other Comprehensive Income (Loss)
AOCI Attributable to Parent, Net of Tax:
Beginning balance	(25,300)	6,254	(28,324)
Net change in accumulated other comprehensive income (loss)	(9,339)	(31,554)	34,578
End of period	(34,639)	(25,300)	6,254
Unrealized Gain (Loss) on Available-for-Sale Securities
AOCI Attributable to Parent, Net of Tax:
Beginning balance, before tax	(91)	(418)	(209)
Other comprehensive income (loss) before reclassifications, before tax	91	327	(209)
Amounts reclassified from accumulated other comprehensive income (loss), before tax	0	0	0
Net current-period other comprehensive income (loss), before tax	91	327	(209)
Ending balance, before tax	0	(91)	(418)
Foreign Currency Translation
AOCI Attributable to Parent, Net of Tax:
Beginning balance, before tax	(18,932)	7,551	(27,236)
Other comprehensive income (loss) before reclassifications, before tax	(9,376)	(26,483)	34,787
Amounts reclassified from accumulated other comprehensive income (loss), before tax	0	0	0
Net current-period other comprehensive income (loss), before tax	(9,376)	(26,483)	34,787
Ending balance, before tax	(28,308)	(18,932)	7,551
Actuarial Gain (Loss) on Pension
AOCI Attributable to Parent, Net of Tax:
Beginning balance, before tax	(5,313)	0	0
Other comprehensive income (loss) before reclassifications, before tax	(1,692)	(5,547)	0
Amounts reclassified from accumulated other comprehensive income (loss), before tax	1,638	234	0
Net current-period other comprehensive income (loss), before tax	(54)	(5,313)	0
Ending balance, before tax	$ (5,367)	$ (5,313)	$ 0

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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