Redeemable Noncontrolling Interests and Equity - Schedule of Changes in Redeemable Noncontrolling Interest,Total Stockholders' Equity and Noncontrolling Interests (Details) $ in Thousands	6 Months Ended
	Jun. 30, 2017 USD ($) fund	Dec. 31, 2016 fund
Stockholders' Equity Attributable to Noncontrolling Interest [Roll Forward]
Balance at beginning of period	$ 137,907
Balance at end of period	163,077
Balance at beginning of period	924,186
Exercise of stock options	529
Issuance of restricted stock units, net of tax withholdings	(2,099)
Shares issued in connection with the Employee Stock Purchase Plan	1,145
Stock based compensation	11,416
Contributions from noncontrolling interests	231,123
Distributions to noncontrolling interests	(19,527)
Cumulative effect of adoption of new ASUs	2,996
Net income (loss)	(95,994)
Other comprehensive loss, net of taxes	(3,569)
Balance at end of period	$ 1,050,206
Number of funds, carrying value adjusted to redemption value | fund	6	4
Redeemable Noncontrolling Interests
Stockholders' Equity Attributable to Noncontrolling Interest [Roll Forward]
Balance at beginning of period	$ 137,907
Contributions from redeemable noncontrolling interests	75,169
Distributions to redeemable noncontrolling interests	(7,666)
Net income (loss) attributable to redeemable noncontrolling interests	(42,333)
Balance at end of period	163,077
Total Stockholders' Equity
Stockholders' Equity Attributable to Noncontrolling Interest [Roll Forward]
Balance at beginning of period	672,961
Exercise of stock options	529
Issuance of restricted stock units, net of tax withholdings	(2,099)
Shares issued in connection with the Employee Stock Purchase Plan	1,145
Stock based compensation	11,416
Cumulative effect of adoption of new ASUs	2,996
Net income (loss)	37,848
Other comprehensive loss, net of taxes	(3,569)
Balance at end of period	721,227
Noncontrolling Interests
Stockholders' Equity Attributable to Noncontrolling Interest [Roll Forward]
Balance at beginning of period	251,225
Contributions from noncontrolling interests	231,123
Distributions to noncontrolling interests	(19,527)
Net income (loss)	(133,842)
Balance at end of period	$ 328,979