Condensed Consolidated Statements of Comprehensive Income (Loss) (Unaudited) - USD ($) $ in Thousands	3 Months Ended
Mar. 28, 2020	Mar. 31, 2019
Statement Of Income And Comprehensive Income [Abstract]
Net (loss) income	$ (4,404)	$ 7,576
Other comprehensive (loss), net of tax:
Change in net unrealized (losses) gains on available-for-sale marketable securities	(526)	95
Change in currency translation adjustments	(2,231)	(518)
Other comprehensive (loss)	(2,757)	(423)
Total comprehensive (loss) income	$ (7,161)	$ 7,153

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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