Variable Interest Entities - Schedule of Revenue and Expenses of CUSO (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Variable Interest Entity [Line Items]
Student services and administrative expenses	$ 84,622	$ 100,440	$ 266,282	$ 297,225
Provision for private education loan losses	754	4,511	5,311	13,582
Interest expense	9,709	9,292	30,088	28,315
Income before provision for income taxes	2,825	$ 14,139	21,761	$ 14,995
CUSO [Member]
Variable Interest Entity [Line Items]
Revenue	1,182		3,431
Student services and administrative expenses	400		1,279
Provision for private education loan losses	877		16
Interest expense	3,364		10,578
Income before provision for income taxes	$ (3,459)		$ (8,442)