XML 35 R25.htm IDEA: XBRL DOCUMENT v3.7.0.1
Fair Value Measurements - Additional Information (Details) - USD ($)
$ in Thousands
Jul. 31, 2017
Jan. 31, 2017
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]    
Restricted cash $ 26,543 $ 26,781
Certificates of Deposit | Level 2    
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]    
Restricted cash $ 26,500 $ 26,800