Restatement and Revision of Previously Issued Unaudited Financial Statements - Additional Information (Detail) (USD $) In Thousands, unless otherwise specified	6 Months Ended	12 Months Ended
Dec. 31, 2012	Dec. 31, 2011
Accounting Changes and Error Corrections [Abstract]
Increase in retained earnings		$ 5,366
Decrease in capital surplus		5,366
Decrease in retained earnings related to recognition of revenue related to students withdrawal from program		306
Decrease in net income	$ 1,008

Decrease In Retained Earnings Due To Cumulative Adjustments For Recognition Of Revenue

No definition available.

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