Student Receivables - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended	9 Months Ended
	Sep. 30, 2012	Sep. 30, 2012	Dec. 31, 2011
Financing Receivable, Allowance for Credit Losses [Line Items]
Student receivables written off period, days past due		Greater than 90 days
Delayed receipt amount	$ 19.7
Student receivables, net of allowance for doubtful accounts and net of deferred tuition revenue	5.0	5.0	6.1
Outstanding net recourse loan receivable	3.0	3.0	3.2
Carrying amount of student receivables held for sale	1.9	1.9
Fair value adjustments of student receivable		$ 0.9