Restructuring - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended
	Jul. 31, 2020	Jul. 31, 2019	Jun. 30, 2020
Restructuring Cost and Reserve [Line Items]
Restructuring charges, net	$ 3,460	$ (19)
Manufacturing Plant Closure
Restructuring Cost and Reserve [Line Items]
Restructuring charges, net	1,800
Employee Severance
Restructuring Cost and Reserve [Line Items]
Restructuring charges, net	1,667
Employee Severance | Nationwide Reductions In Force
Restructuring Cost and Reserve [Line Items]
Restructuring charges, net	1,700
Employee Severance | Manufacturing Plant Closure
Restructuring Cost and Reserve [Line Items]
Restructuring charges, net	400
Other Restructuring | Manufacturing Plant Closure
Restructuring Cost and Reserve [Line Items]
Restructuring charges, net	$ 1,400
Minimum | Manufacturing Plant Closure
Restructuring Cost and Reserve [Line Items]
Expected restructuring costs			$ 3,000
Minimum | Employee Severance | Manufacturing Plant Closure
Restructuring Cost and Reserve [Line Items]
Expected restructuring costs			500
Minimum | Other Restructuring | Manufacturing Plant Closure
Restructuring Cost and Reserve [Line Items]
Expected restructuring costs			2,500
Maximum | Manufacturing Plant Closure
Restructuring Cost and Reserve [Line Items]
Expected restructuring costs			5,000
Maximum | Employee Severance | Manufacturing Plant Closure
Restructuring Cost and Reserve [Line Items]
Expected restructuring costs			1,000
Maximum | Other Restructuring | Manufacturing Plant Closure
Restructuring Cost and Reserve [Line Items]
Expected restructuring costs			$ 4,000