Revenue - Remaining Performance Obligation (Details) - USD ($) $ in Millions	Jul. 31, 2021	Apr. 30, 2021
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue expected to be recognized from remaining performance obligations, amount	$ 290.6	$ 293.8
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2021-05-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue expected to be recognized from remaining performance obligations, amount		$ 145.2
Revenue expected to be recognized from remaining performance obligations, period
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2021-08-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue expected to be recognized from remaining performance obligations, amount	$ 145.0
Revenue expected to be recognized from remaining performance obligations, period	12 months
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2022-08-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue expected to be recognized from remaining performance obligations, period