Reportable Segments - Narrative (Details) $ in Millions	12 Months Ended
	Apr. 30, 2020 USD ($) Segment Industry	Apr. 30, 2019 USD ($)	Apr. 30, 2018
Concentration Risk [Line Items]
Number of industries in which Company operates | Industry	1
Number of reportable segments | Segment	4
Trade receivables, less allowance for doubtful accounts	$ 551.4	$ 503.8
Wal-Mart Stores, Inc. [Member] | Major Customer [Member]
Concentration Risk [Line Items]
Trade receivables, less allowance for doubtful accounts	$ 131.9	$ 137.7
Wal-Mart Stores, Inc. [Member] | Major Customer [Member] | Revenue from Contract with Customer [Member]
Concentration Risk [Line Items]
Percentage of concentration risk	32.00%	32.00%	31.00%