Corporate Debt - Schedule of Corporate Debt (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Debt Instrument [Line Items]
Unpaid principle balance of debt	$ 2,197,630
Capital leases	0	$ 480
Total corporate debt	2,129,000	2,157,424
2013 Term Loan [Member]
Debt Instrument [Line Items]
Unpaid principle balance of debt		1,416,500	$ 1,423,750
Amortized Cost of Debt	$ 1,394,658	$ 1,396,884
Weighted Average Stated Interest Rate	4.75%	4.75%
Senior Notes [Member]
Debt Instrument [Line Items]
Unpaid principle balance of debt		$ 538,662	538,662
Amortized Cost of Debt	$ 529,738	$ 528,337
Weighted Average Stated Interest Rate	7.875%	7.875%
Convertible Notes [Member]
Debt Instrument [Line Items]
Unpaid principle balance of debt		$ 242,468	$ 290,000
Amortized Cost of Debt	$ 204,604	$ 231,723
Weighted Average Stated Interest Rate	4.50%	4.50%