Quarterly report pursuant to Section 13 or 15(d)

Fee Revenue - Additional Information (Detail)

Fee Revenue - Additional Information (Detail)
$ in Millions
3 Months Ended
Jul. 31, 2021
USD ($)
Revenue From Contract With Customer [Abstract]  
Contract liabilities, revenue recognized $ 64.0
Revenue recognized, remaining performance obligation $ 804.2
Revenue, practical expedient, initial application and transition, completed contract, same reporting period true
Revenue, remaining performance obligation, optional exemption, performance obligation true