CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS) - USD ($) $ in Thousands	12 Months Ended
	Dec. 28, 2019	Dec. 29, 2018	Dec. 30, 2017
Statement of Comprehensive Income [Abstract]
Net loss	$ (386,618)	$ (214,295)	$ (194,506)
Other comprehensive income (loss):
Net unrealized gain (loss) on investments	91	327	(209)
Foreign currency translation adjustment	(9,376)	(26,483)	34,787
Tax effect on items related to available-for-sale investments	0	(85)	0
Actuarial loss on pension liabilities	(54)	(5,313)	0
Net change in accumulated other comprehensive income (loss)	(9,339)	(31,554)	34,578
Comprehensive loss	$ (395,957)	$ (245,849)	$ (159,928)