Debt - Debt Extinguishment - Narrative (Details) - USD ($)
$ in Thousands
3 Months Ended
Mar. 31, 2017
Mar. 31, 2016
Dec. 31, 2016
Debt Instrument [Line Items]      
Loss on debt extinguishment $ (30) $ (5,341)  
Master Trust Notes      
Debt Instrument [Line Items]      
Debt extinguishment costs $ 49,200 103,800  
Weighted average contractual interest rate (as a percent) 5.69%   6.72%
Loss on debt extinguishment   $ (5,300)