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Net Loss Per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 30, 2018	Sep. 30, 2018	Jul. 01, 2018	Apr. 01, 2018	Dec. 31, 2017	Oct. 01, 2017	Jul. 02, 2017	Apr. 02, 2017	Dec. 30, 2018	Dec. 31, 2017	Jan. 01, 2017
Earnings Per Share, Diluted, by Common Class, Including Two Class Method [Line Items]
Net loss attributable to stockholders	$ (158,174)	$ (89,826)	$ (447,117)	$ (115,974)	$ (572,651)	$ (46,229)	$ (90,515)	$ (219,725)	$ (811,091)	$ (929,121)	$ (448,635)
Basic and diluted weighted-average shares (in shares)									140,825	139,370	137,985
Basic and diluted net loss per share attributable to stockholders (in dollars per share)	$ (1.12)	$ (0.64)	$ (3.17)	$ (0.83)	$ (4.10)	$ (0.33)	$ (0.65)	$ (1.58)	$ (5.76)	$ (6.67)	$ (3.25)
Stock options
Earnings Per Share, Diluted, by Common Class, Including Two Class Method [Line Items]
Outstanding anti-dilutive potential common stock excluded from income (loss) per diluted share									0	0	141
Restricted stock units
Earnings Per Share, Diluted, by Common Class, Including Two Class Method [Line Items]
Outstanding anti-dilutive potential common stock excluded from income (loss) per diluted share									5,699	3,917	4,997
Upfront Warrants (held by Total)
Earnings Per Share, Diluted, by Common Class, Including Two Class Method [Line Items]
Outstanding anti-dilutive potential common stock excluded from income (loss) per diluted share									9,532	364	3,721
4.00% debentures due 2023
Earnings Per Share, Diluted, by Common Class, Including Two Class Method [Line Items]
Outstanding anti-dilutive potential common stock excluded from income (loss) per diluted share									13,922	13,922	13,922
0.75% debentures due 2018
Earnings Per Share, Diluted, by Common Class, Including Two Class Method [Line Items]
Outstanding anti-dilutive potential common stock excluded from income (loss) per diluted share									4,975	12,026	12,026
0.875% debentures due 2021
Earnings Per Share, Diluted, by Common Class, Including Two Class Method [Line Items]
Outstanding anti-dilutive potential common stock excluded from income (loss) per diluted share									8,203	8,203	8,203