Variable Interests - Guarantee and Other Payments Related to PEAKS Program (Detail) (PEAKS Guarantee [Member], USD $) In Thousands, unless otherwise specified	3 Months Ended	9 Months Ended
Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
PEAKS Guarantee [Member]
Variable Interest Entity [Line Items]
Guarantee	$ 138	$ 243	$ 1,377	$ 502
Payments on Behalf of Borrowers	2,502	0	7,647	0
Total	$ 2,640	$ 243	$ 9,024	$ 502

Amount of guarantee and other payments made to a third party during the period.

No definition available.

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