Consolidated Statements of Stockholders' Equity - USD ($) $ in Thousands	Total	Common Stock [Member]	Additional Paid-In Capital [Member]	Treasury Stock [Member]	OCI [Member]	Retained Earnings (Accumulated Deficit) [Member]
Beginning balance, Value at Dec. 31, 2013	$ 1,877,271	$ 5	$ 2,823,738		$ (1,046)	$ (945,426)
Beginning balance, Shares at Dec. 31, 2013		832,309,000
Exercise of stock options, warrants and ESPP	16,421		16,421
Exercise of stock options, warrants and ESPP, Shares		11,461,000
Vesting of ZSUs, net	(1,218)		(429)	$ (789)
Vesting of ZSUs, net, Shares		22,582,000
Issuance of common stock in connection with business acquisitions	131,158		131,158
Issuance of common stock in connection with business acquisitions, Shares		39,754,000
Cancellation of unvested restricted common stock, Shares		(200,000)
Stock-based expense	126,856		126,856
Vesting of common stock following the early exercise of options	341		341
Retirement of treasury stock, net of repurchases				789		(789)
Retirement of treasury stock, net of repurchases, Shares		(46,000)
Tax cost (benefit) from stock-based expense	(1,108)		(1,108)
Net income (loss)	(225,900)					(225,900)
Other comprehensive income (loss)	(28,129)				(28,129)
Ending balance, Value at Dec. 31, 2014	1,895,692	$ 5	3,096,977		(29,175)	(1,172,115)
Ending balance, Shares at Dec. 31, 2014		905,860,000
Exercise of stock options, warrants and ESPP	7,567		7,567
Exercise of stock options, warrants and ESPP, Shares		7,075,000
Vesting of ZSUs, net	(2,901)	$ 1	(2,130)	(772)
Vesting of ZSUs, net, Shares		27,966,000
Contributed capital, related to common control acquisition	(109)		1,854			(1,963)
Stock-based expense	129,591		129,591
Stock-based expense, Shares		717,000
Vesting of common stock following the early exercise of options	170		170
Repurchases of common stock	(98,902)			(98,902)
Repurchases of common stock, Shares		(38,001,000)
Retirement of treasury stock, net of repurchases				732		(732)
Tax cost (benefit) from stock-based expense	516		516
Net income (loss)	(121,510)					(121,510)
Other comprehensive income (loss)	(23,213)				(23,213)
Ending balance, Value at Dec. 31, 2015	1,786,901	$ 6	3,234,545	(98,942)	(52,388)	(1,296,320)
Ending balance, Shares at Dec. 31, 2015		903,617,000
Exercise of stock options, warrants and ESPP	5,921		5,921
Exercise of stock options, warrants and ESPP, Shares		6,989,000
Vesting of ZSUs, net	(3,423)		(2,582)	(841)
Vesting of ZSUs, net, Shares		30,794,000
Stock-based expense	111,824		111,824
Repurchases of common stock	(136,080)			(136,080)
Repurchases of common stock, Shares		(54,550,000)
Retirement of treasury stock, net of repurchases				$ 235,863		(235,863)
Net income (loss)	(108,173)					(108,173)
Other comprehensive income (loss)	(76,306)				(76,306)
Ending balance, Value at Dec. 31, 2016	$ 1,580,664	$ 6	$ 3,349,708		$ (128,694)	$ (1,640,356)
Ending balance, Shares at Dec. 31, 2016		886,850,000