Consolidated Statements of Comprehensive Income (Loss) - USD ($) $ in Thousands	12 Months Ended
Sep. 27, 2019	Sep. 28, 2018	Sep. 29, 2017
Statement of Comprehensive Income [Abstract]
Net loss	$ (383,798)	$ (139,977)	$ (169,493)
Unrealized gain (loss) on short-term investments, net of tax	477	(287)	(63)
Foreign currency translation gain (loss), net of tax	1,693	(502)	(5,999)
Other comprehensive income (loss), net of tax	2,170	(789)	(6,062)
Total comprehensive loss	$ (381,628)	$ (140,766)	$ (175,555)

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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Amount after tax and reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature.

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