Annual report pursuant to Section 13 and 15(d)

Fee Revenue - Additional Information (Detail)

v3.22.2
Fee Revenue - Additional Information (Detail) - USD ($)
$ in Millions
12 Months Ended
Apr. 30, 2022
Apr. 30, 2021
Apr. 30, 2020
Revenue From Contract With Customer [Abstract]      
Contract liabilities, revenue recognized $ 131.3 $ 92.4 $ 94.1
Revenue, practical expedient, initial application and transition, completed contract, same reporting period true    
Revenue, remaining performance obligation, optional exemption, performance obligation true    
Revenue recognized, remaining performance obligation $ 1,034.9