Consolidated Statements of Comprehensive Loss (Unaudited) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Statement Of Income And Comprehensive Income [Abstract]
Net loss	$ (293,188)	$ (184,227)	$ (575,455)	$ (338,408)
Other comprehensive income (loss):
Unrealized net gain on derivatives and short-term marketable securities, net of tax	22,928	4	43,733	208
Foreign currency translation adjustment	(2,300)	1,157	(5,984)	(14,990)
Other comprehensive income (loss)	20,628	1,161	37,749	(14,782)
Comprehensive loss	$ (272,560)	$ (183,066)	$ (537,706)	$ (353,190)