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Basic and Diluted Net Loss Per Common Share - Computation of Net Income (Loss) Per Common Share Basic and Diluted (Detail) - USD ($) $ / shares in Units, shares in Thousands	3 Months Ended								12 Months Ended
	Dec. 28, 2019	Sep. 28, 2019	Jun. 29, 2019	Mar. 30, 2019	Dec. 29, 2018	Sep. 29, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 28, 2019	Dec. 29, 2018	Dec. 30, 2017	May 31, 2018
Earnings Per Share, Basic, by Common Class, Including Two Class Method [Line Items]
Net loss	$ (66,594,000)	$ (84,767,000)	$ (113,656,000)	$ (121,601,000)	$ (133,467,000)	$ (32,610,000)	$ (21,938,000)	$ (26,280,000)	$ (386,618,000)	$ (214,295,000)	$ (194,506,000)
Weighted average common shares outstanding - basic and diluted (in shares)									178,984	157,748	147,878
Net loss per common share - basic and diluted (in dollars per share)									$ (2.16)	$ (1.36)	$ (1.32)
1.75% Convertible Senior Notes Due June 1, 2018
Earnings Per Share, Basic, by Common Class, Including Two Class Method [Line Items]
Principal amount												$ 150,000,000.0
Debt instrument interest percentage	1.75%								1.75%			1.75%