Consolidated Statements of Comprehensive Loss (Unaudited) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Statement Of Income And Comprehensive Income [Abstract]
Net loss	$ (229,858)	$ (74,708)	$ (568,266)	$ (186,411)
Other comprehensive income (loss), net of tax:
Unrealized net gain on short-term marketable securities	11		219
Foreign currency translation adjustment	(9,192)		(24,182)
Other comprehensive loss	(9,181)		(23,963)
Comprehensive loss	$ (239,039)	$ (74,708)	$ (592,229)	$ (186,411)