Condensed Consolidated Statements of Comprehensive (Loss) Income (Unaudited) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Apr. 03, 2020	Mar. 29, 2019	Apr. 03, 2020	Mar. 29, 2019
Statement of Comprehensive Income [Abstract]
Net loss	$ (10,226)	$ (46,204)	$ (38,588)	$ (69,600)
Unrealized (loss) gain on short-term investments, net of tax	(1,376)	606	(1,297)	350
Foreign currency translation (loss) gain, net of tax	(687)	351	(935)	1,260
Other comprehensive (loss) income, net of tax	(2,063)	957	(2,232)	1,610
Total comprehensive loss	$ (12,289)	$ (45,247)	$ (40,820)	$ (67,990)

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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