Condensed Consolidated Statements of Comprehensive Loss (unaudited) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Statement of Comprehensive Income [Abstract]
Net loss attributable to Class A and Class B stockholders	$ (34,903)	$ (78,579)	$ (181,560)	$ (141,972)
Other comprehensive income (loss), net of taxes:
Unrealized gain (loss) on available-for-sale securities	(12)	1	14	25
Change in derivative instruments designated and qualifying in cash flow hedges	(2,444)	1,236	(8,137)	5,156
Other comprehensive income (loss), net of taxes	(2,456)	1,237	(8,123)	5,181
Comprehensive loss	(37,359)	(77,342)	(189,683)	(136,791)
Comprehensive (income) loss attributable to noncontrolling interests and redeemable noncontrolling interests	2,457	(1,182)	7,845	(4,745)
Comprehensive loss attributable to Class A and Class B stockholders	$ (34,902)	$ (78,524)	$ (181,838)	$ (141,536)