Student Receivables - Changes in Current and Non-Current Receivables Allowance (Parenthetical) (Detail) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Receivables [Abstract]
Recoveries of amounts previously written off	$ 6.2	$ 6.7	$ 8.5

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