Student Receivables - Changes in Current and Non-Current Receivables Allowance (Parenthetical) (Detail) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2017	Mar. 31, 2016
Receivables [Abstract]
Recoveries of amounts previously written off	$ 1.5	$ 2.0

The cash inflow from loans reinstated and recovered that were previously deemed uncollectible.

No definition available.

Name:	us-gaap_ProceedsFromRecoveriesOfLoanPreviouslyChargedOff
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration