Stockholders' Equity - Net Transfers (To) From Navient (Details) (USD $)	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Schedule of Transfers To and From Affiliate [Line Items]
Total capital contributions		$ 43,500,000
Corporate push-down		5,738,000
Net change in income tax accounts		15,659,000
Net change in receivable/payable		(47,622,000)
Other		(31,000)
Total net transfers from the entity that is now a subsidiary of Navient	0	17,244,000
Loan origination activities
Schedule of Transfers To and From Affiliate [Line Items]
Total capital contributions		25,268,000
Loan sales
Schedule of Transfers To and From Affiliate [Line Items]
Total capital contributions		45,000
Corporate overhead activities
Schedule of Transfers To and From Affiliate [Line Items]
Total capital contributions		17,755,000
Other
Schedule of Transfers To and From Affiliate [Line Items]
Total capital contributions		$ 432,000