Shareholders' Equity - Noncontrolling Interest Reflected in Consolidated Statement of Operations (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Class of Stock [Line Items]
Net income (loss) attributable to noncontrolling interest	$ 3,751	$ 14,353	$ 14,965
Series C Convertible Units
Class of Stock [Line Items]
Net income (loss) attributable to noncontrolling interest	3,027	18,792	18,600
Class A Units
Class of Stock [Line Items]
Net income (loss) attributable to noncontrolling interest	(6,417)	(4,282)	(3,372)
Series D Convertible Units
Class of Stock [Line Items]
Net income (loss) attributable to noncontrolling interest	134	0	0
Noncontrolling interest, beneficial conversion feature	7,569	0	0
Consolidated Subsidiaries With Noncontrolling Interest
Class of Stock [Line Items]
Net income (loss) attributable to noncontrolling interest	$ (562)	$ (157)	$ (263)