Intangibles (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended
	Jul. 31, 2019	Jul. 31, 2018
Finite-Lived Intangible Assets [Line Items]
Amortization expense	$ 12.3	$ 12.3
Customer relationships
Finite-Lived Intangible Assets [Line Items]
Intangible assets estimated useful lives	6 years
Trademarks
Finite-Lived Intangible Assets [Line Items]
Intangible assets estimated useful lives	3 years