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Derivative Instruments - Additional Information (Details) - Foreign currency forward - USD ($)
$ in Millions
3 Months Ended 12 Months Ended
Apr. 30, 2020
Apr. 30, 2020
Jan. 31, 2020
Derivative [Line Items]      
Gains (losses) expected to be reclassified out of OCI within the next 12 months $ 0.1    
Designated as hedging | Cash flow hedging      
Derivative [Line Items]      
Notional values 5.1 $ 5.1 $ 5.8
Maturity term (not greater than)   13 months 13 months
Not designated as hedging      
Derivative [Line Items]      
Notional values $ 25.3 $ 25.3 $ 23.5
Maturity term (not greater than)   13 months