CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY - USD ($) shares in Thousands, $ in Thousands	Total	Common Stock	Additional Paid-in Capital	Company Stock Held By NQDC	Accumulated Other Comprehensive Income (Loss)	Accumulated Other Comprehensive Income (Loss) Previously Reported	Accumulated Deficit
Beginning Balance (in shares) at Dec. 31, 2016		172,648
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuances under equity incentive plans, net of tax (in shares)		2,092
Conversion of convertible notes, net (in shares)		1,104
Ending Balance (in shares) at Dec. 31, 2017		175,844
Beginning Balance at Dec. 31, 2016	$ 2,766,275	$ 173	$ 4,288,113	$ (14,321)	$ 12,816		$ (1,520,506)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuances under equity incentive plans, net of tax		2	27,350
Conversion of convertible notes, net		1	22,476
Stock-based compensation			145,281
Common stock held by the NQDC			0	97
Accounting impact of NQDC Plan Change			0	0
Other comprehensive income (loss)	(35,777)
Net loss	(117,042)						(117,042)
Ending Balance at Dec. 31, 2017	2,808,663	$ 176	4,483,220	(14,224)	(23,547)	$ (22,961)	(1,637,548)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuances under equity incentive plans, net of tax (in shares)		2,314
Conversion of convertible notes, net (in shares)		95
Ending Balance (in shares) at Dec. 31, 2018		178,253
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuances under equity incentive plans, net of tax		$ 2	31,583
Conversion of convertible notes, net		0	(16)
Stock-based compensation			155,139
Common stock held by the NQDC			0	923
Accounting impact of NQDC Plan Change			0	0
Other comprehensive income (loss)	28,818
Net loss	(77,211)						(77,211)
Ending Balance at Dec. 31, 2018	2,967,940	$ 178	4,669,926	(13,301)	5,271		(1,694,134)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuances under equity incentive plans, net of tax (in shares)		1,585
Conversion of convertible notes, net (in shares)		0
Ending Balance (in shares) at Dec. 31, 2019		179,838
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuances under equity incentive plans, net of tax		$ 2	(11,071)
Conversion of convertible notes, net		0	0
Stock-based compensation			163,891
Common stock held by the NQDC			(692)	692
Accounting impact of NQDC Plan Change			10,653	2,648
Other comprehensive income (loss)	14,893
Net loss	(23,848)						(23,848)
Ending Balance at Dec. 31, 2019	$ 3,122,381	$ 180	$ 4,832,707	$ (9,961)	$ 20,164		$ (1,720,709)