Other Income (Expense) - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Other Income (Expense) [Line Items]
Effective interest rate	4.90%		4.90%
Litigation settlement proceeds	$ 0	$ 0	$ 12,548	$ 0
Fees and expenses for the resolved SEC investigation	$ 0	$ 7,430	$ 0	$ 7,430
Minimum
Other Income (Expense) [Line Items]
Retained interest, effective interest rate			3.70%
Maximum
Other Income (Expense) [Line Items]
Retained interest, effective interest rate			11.30%