Commitments and Contingencies - Additional Information (Detail) - USD ($)							1 Months Ended					3 Months Ended				6 Months Ended			12 Months Ended
	Jun. 10, 2015	Jun. 08, 2015	Mar. 19, 2015	Nov. 12, 2014	Oct. 09, 2014	Mar. 26, 2012	Dec. 31, 2014	Sep. 30, 2014	Mar. 31, 2014	Jan. 31, 2014	Apr. 30, 2013	Jun. 30, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Jun. 30, 2015	Sep. 30, 2014	Jun. 30, 2014	Dec. 31, 2014	Dec. 31, 2013	Oct. 31, 2014	Feb. 28, 2013
Loss Contingencies [Line Items]
Face amount of surety bonds												$ 21,000,000				$ 21,000,000
Letter of credit payable												82,001,000				$ 82,001,000
Letter of credit payable																					$ 79,708,000
Letter of credit termination date																Nov. 04, 2019
Payments under PEAK Guarantee																			$ 159,300,000
Payments on Behalf of Borrowers																			1,832,000
Collateral maintained with bank for education loan							$ 8,600,000				$ 8,600,000	8,600,000	$ 8,600,000		$ 8,600,000	$ 8,600,000		$ 8,600,000	8,600,000
Increase in collateral maintained in restricted bank account																2,600,000
Additional payments expected in 2018												70,908,000				70,908,000
Estimated regular payment made																41,632,000
Offset amounts relating to guarantee obligations												0			0	$ 0		0
Life of private education loan made under CUSO Student Loan																10 years
Litigation settlement amount						$ 395,000
Revolving Note [Member]
Loss Contingencies [Line Items]
Credit facility outstanding, amount												8,200,000				$ 8,200,000
Letter of Credit Issued to Insurers and Agencies [Member]
Loss Contingencies [Line Items]
Letter of credit payable												2,293,000				2,293,000
Payable in 2018 through 2026 [Member]
Loss Contingencies [Line Items]
Estimated regular payment made																93,776,000
Payable 2022 through 2026 [Member]
Loss Contingencies [Line Items]
Estimated regular payment made																16,200,000
CUSO Program [Member]
Loss Contingencies [Line Items]
Principal amount for private education loans												141,000,000				141,000,000
PEAKS Guarantee [Member]
Loss Contingencies [Line Items]
Payments under PEAK Guarantee																20,457,000	$ 2,700,000		161,100,000
Future recovery of PEAKS guarantee payments												40,500,000				40,500,000
Payments under PEAK Guarantee with respect to Asset/Liability Ratio					$ 50,000,000						$ 60,340,000		$ 64,900,000	$ 51,700,000
Payments on Behalf of Borrowers										$ 1,800,000
PEAKS Guarantee [Member] | Letter Agreement [Member]
Loss Contingencies [Line Items]
Payments under PEAK Guarantee									$ 40,000,000
CUSO RSA [Member]
Loss Contingencies [Line Items]
Discharge Payments												6,544,000			0	9,253,000		0
Net guarantee obligation payments												8,104,000			1,589,000	13,093,000		2,747,000
Recoveries from charged-off loans																521,000
Regular Payments												1,560,000			1,589,000	3,840,000		2,747,000
PEAKS Senior Debt [Member]
Loss Contingencies [Line Items]
Outstanding balance												71,892,000				71,892,000						$ 257,533,000
Payments under PEAK Guarantee with respect to Asset/Liability Ratio							$ 64,900,000	$ 51,700,000								20,457,000			156,600,000
PEAKS Senior Debt [Member] | Letter Agreement [Member]
Loss Contingencies [Line Items]
Payments under PEAK Guarantee									$ 40,000,000
Fourth Amendment [Member] | CUSO RSA [Member]
Loss Contingencies [Line Items]
Discharge Payments				$ 2,577,000
Fifth Amendment [Member] | CUSO RSA [Member]
Loss Contingencies [Line Items]
Discharge Payments			$ 2,709,000
Sixth Amendment [Member] | CUSO RSA [Member]
Loss Contingencies [Line Items]
Discharge Payments	$ 6,544,000
Accrued interest rate		12.50%
Reduction amount in Regular Payments	$ 2,000,000
Period from July 1, 2015 through December 31, 2015 [Member] | PEAKS Guarantee [Member]
Loss Contingencies [Line Items]
Payments under PEAK Guarantee																10,300,000
Year 2016 [Member] | PEAKS Guarantee [Member]
Loss Contingencies [Line Items]
Payments under PEAK Guarantee																5,300,000
Year 2017 [Member] | PEAKS Guarantee [Member]
Loss Contingencies [Line Items]
Payments under PEAK Guarantee																60,000
Year 2020 [Member] | PEAKS Guarantee [Member]
Loss Contingencies [Line Items]
Payments under PEAK Guarantee																15,300,000
Year 2020 [Member] | PEAKS Senior Debt [Member] | PEAKS Guarantee [Member]
Loss Contingencies [Line Items]
Outstanding balance												0				0
Year 2015 [Member] | PEAKS Senior Debt [Member] | PEAKS Guarantee [Member]
Loss Contingencies [Line Items]
Outstanding balance												56,400,000				56,400,000
CUSO [Member]
Loss Contingencies [Line Items]
Recoveries from charged-off loans												0			$ 256,000	0		$ 475,000	475,000
Offset amounts relating to guarantee obligations																				$ 8,472,000
Amount of offset to repay																9,500,000
Recoveries from charged-off loans																1,049,000
CUSO [Member] | CUSO RSA [Member]
Loss Contingencies [Line Items]
Net guarantee obligation payments																			9,139,000
Regular Payments																			7,028,000
Recoveries from charged-off loans																			466,000
CUSO [Member] | Fourth Amendment [Member] | CUSO RSA [Member]
Loss Contingencies [Line Items]
Discharge Payments																			$ 2,577,000
Minimum [Member]
Loss Contingencies [Line Items]
Estimated decrease in unrecognized tax benefits												0				0
Minimum [Member] | Payable 2018 through 2021 [Member]
Loss Contingencies [Line Items]
Estimated regular payment made																18,600,000
Maximum [Member]
Loss Contingencies [Line Items]
Estimated decrease in unrecognized tax benefits												$ 6,818,000				6,818,000
Maximum [Member] | Payable 2018 through 2021 [Member]
Loss Contingencies [Line Items]
Estimated regular payment made																$ 20,000,000