Acquisitions and Developments - Pro Forma Results (Details) - NSH - USD ($) $ in Thousands	4 Months Ended	8 Months Ended	12 Months Ended
	Dec. 31, 2017	Aug. 31, 2017	Dec. 31, 2016
Business Acquisition [Line Items]
Net revenues	$ 592,604
Net income	4,477
Less: Net income attributable to non-controlling interests	(39,634)
Net income	$ (35,157)
Predecessor
Business Acquisition [Line Items]
Net revenues		$ 1,122,326	$ 1,679,254
Net income		63,269	132,699
Less: Net income attributable to non-controlling interests		(65,122)	(112,123)
Net income		$ (1,853)	$ 20,576