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Credit Losses - Additional Information (Details) - Investment
Jul. 31, 2021
Apr. 30, 2021
Commercial Paper    
Fair Value And Unrealized Losses On Available For Sale Debt Securities [Line Items]    
Debt securities, available-for-sale, unrealized loss position, number of investments 13 18
Corporate Notes/Bonds    
Fair Value And Unrealized Losses On Available For Sale Debt Securities [Line Items]    
Debt securities, available-for-sale, unrealized loss position, number of investments 19 15