CONDENSED CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY - USD ($) shares in Thousands, $ in Thousands		Total		Common Stock		Additional Paid-in Capital		Treasury Stock		Company Stock Held By NQDC		Accumulated other comprehensive income (loss)		Accumulated Deficit		Accumulated Deficit Impact of change in accounting principles
Beginning balance (in shares) at Dec. 31, 2018	[1]			178,253
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuances under equity incentive plans (in shares)				1,351
Repurchase of common stock (in shares)				0
Ending balance (in shares) at Sep. 30, 2019				179,604
Beginning balance at Dec. 31, 2018		$ 2,967,940	[1]	$ 178	[1]	$ 4,669,926	[1]	$ 0	[1]	$ (13,301)	[1]	$ 5,271	[1]	$ (1,694,134)	[1]	$ (2,727)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuances under equity incentive plans, net of tax				2		(19,183)
Stock-based compensation						122,212
Repurchase of common stock						0		0
Common stock held by the NQDC						(692)				692
Retirement of treasury stock								0
Accounting impact of NQDC Plan change						10,653				2,648
Other comprehensive income (loss)												31,732
Net income (loss)		(38,872)												(38,872)
Ending balance at Sep. 30, 2019		3,074,405		$ 180		4,782,916		0		(9,961)		37,003		(1,735,733)
Beginning balance (in shares) at Jun. 30, 2019	[1]			179,433
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuances under equity incentive plans (in shares)				171
Repurchase of common stock (in shares)				0
Ending balance (in shares) at Sep. 30, 2019				179,604
Beginning balance at Jun. 30, 2019		2,960,954	[1]	$ 179	[1]	4,744,316	[1]	0	[1]	(10,211)	[1]	17,439	[1]	(1,790,769)	[1]	0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuances under equity incentive plans, net of tax				1		(1,294)
Stock-based compensation						40,144
Repurchase of common stock						0		0
Common stock held by the NQDC						(250)				250
Retirement of treasury stock								0
Accounting impact of NQDC Plan change						0				0
Other comprehensive income (loss)												19,564
Net income (loss)		55,036												55,036
Ending balance at Sep. 30, 2019		3,074,405		$ 180		4,782,916		0		(9,961)		37,003		(1,735,733)
Beginning balance (in shares) at Dec. 31, 2019	[1]			179,838
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuances under equity incentive plans (in shares)				2,172
Repurchase of common stock (in shares)				(518)
Ending balance (in shares) at Sep. 30, 2020				181,492
Beginning balance at Dec. 31, 2019		3,122,381	[1],[2]	$ 180	[1]	4,832,707	[1]	0	[1]	(9,961)	[1]	20,164	[1]	(1,720,709)	[1]	0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuances under equity incentive plans, net of tax				1		17,601
Stock-based compensation						136,688
Repurchase of common stock						(50,000)		(50,000)
Common stock held by the NQDC						795				(795)
Retirement of treasury stock								50,000
Accounting impact of NQDC Plan change						0				0
Other comprehensive income (loss)												(9,779)
Net income (loss)		837,001												837,001
Ending balance at Sep. 30, 2020		4,053,893		$ 181		4,937,791		0		(10,756)		10,385		(883,708)
Beginning balance (in shares) at Jun. 30, 2020	[1]			181,148
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuances under equity incentive plans (in shares)				344
Repurchase of common stock (in shares)				0
Ending balance (in shares) at Sep. 30, 2020				181,492
Beginning balance at Jun. 30, 2020		3,236,679	[1]	$ 181	[1]	4,885,637	[1]	0	[1]	(10,678)	[1]	30,050	[1]	(1,668,511)	[1]	$ 0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuances under equity incentive plans, net of tax				0		7,319
Stock-based compensation						44,757
Repurchase of common stock						0		0
Common stock held by the NQDC						78				(78)
Retirement of treasury stock								0
Accounting impact of NQDC Plan change						0				0
Other comprehensive income (loss)												(19,665)
Net income (loss)		784,803												784,803
Ending balance at Sep. 30, 2020		$ 4,053,893		$ 181		$ 4,937,791		$ 0		$ (10,756)		$ 10,385		$ (883,708)

[1] The beginning balances for the nine-month periods were derived from the audited Consolidated Financial Statements included in Company’s Annual Report on Form 10-K for the years ended December 31, 2019 and 2018, respectively, filed with the SEC on February 27, 2020.

[2] December 31, 2019 balances were derived from the audited Consolidated Financial Statements included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2019, filed with the SEC on February 27, 2020.