Unaudited Condensed Consolidated Statements of Comprehensive Income (Loss) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 29, 2019	Sep. 30, 2018	Sep. 29, 2019	Sep. 30, 2018
Statement of Comprehensive Income [Abstract]
Net loss	$ (30,590)	$ (13,225)	$ (105,566)	$ (36,410)
Other comprehensive income (loss), before tax:
Unrealized gain (loss) on derivative instruments	22	20	0	20
Unrealized gain (loss) on available-for-sale securities	(27)	(4)	46	(4)
Total other comprehensive income (loss), before tax	(5)	16	46	16
Tax benefit (provision) related to derivative instruments	0	(3)	0	(3)
Tax benefit (provision) related to available-for-sale securities	0	1	0	1
Total other comprehensive income (loss), net of tax	(5)	14	46	14
Comprehensive loss	$ (30,595)	$ (13,211)	$ (105,520)	$ (36,396)

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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