Loans Held for Investment - Additional Information (Detail)	9 Months Ended	12 Months Ended
	Sep. 30, 2014	Dec. 31, 2013	Jul. 01, 2006	Jun. 30, 2006
Receivables [Abstract]
Percent of Private Loans indexed to LIBOR	83.00%
Tier One of Government Guarantee	97.00%		97.00%
Tier Two of Government Guarantee				98.00%
Estimated weighted average life of student loans	6 years 8 months 6 days	7 years
Tier 3 of Government Guarantee	100.00%