Accumulated Other Comprehensive Loss (Details) - USD ($) $ in Thousands	Sep. 29, 2018	Dec. 30, 2017
Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract]
Foreign currency translation loss	$ (19,213)	$ (2,976)
Changes in defined benefit plan liabilities	(3,138)	(3,292)
Unrealized holding gains on available-for-sale securities	0	2,638
Total accumulated other comprehensive income loss	$ (22,351)	$ (3,630)

Accumulated adjustment, net of tax, that results from the process of translating subsidiary financial statements and foreign equity investments into the reporting currency from the functional currency of the reporting entity, net of reclassification of realized foreign currency translation gains or losses.

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