Contingencies - Aggregate Amount of Guarantee Payments, Discharge Payments and Payments on Behalf of Borrowers (Parenthetical) (Detail) - PEAKS Program [Member] $ in Thousands	3 Months Ended
	Mar. 31, 2013 USD ($)
Schedule of Claims and Contingencies [Line Items]
Guarantee payments paid to prior consolidation	$ 854
Payments on behalf of borrowers prior to consolidation	$ 532