Commitments and Contingencies - Aggregate Amount of Guarantee Payments, Discharge Payments and Payments on Behalf of Borrowers (Parenthetical) (Detail) - Jun. 30, 2015 - USD ($) $ in Thousands	Total	Total
CUSO RSA [Member]
Schedule of Claims and Contingencies [Line Items]
Recoveries from charged-off loans owed related to regular payments obligation	$ 231	$ 521

The amount of recoveries from charged-off loans that were owed to the reporting entity by the variable interest entity that were offset against amounts the reporting entity owed to the variable interest entity.

No definition available.

Name:	esi_RecoveriesOwedToReportingEntityOffsetAgainstAmountsOwedToVariableInterestEntity
Namespace Prefix:	esi_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration