XML 29 R47.htm IDEA: XBRL DOCUMENT v3.3.0.814
Student Receivables - Changes in Current and Non-Current Receivables Allowance (Parenthetical) (Detail) - USD ($)
$ in Millions
3 Months Ended 9 Months Ended
Sep. 30, 2015
Sep. 30, 2014
Sep. 30, 2015
Sep. 30, 2014
Receivables [Abstract]        
Recoveries of amounts previously written off $ 1.0 $ 1.4 $ 3.3 $ 4.5