Restructuring Charges (Narrative) (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Jan. 31, 2022	Apr. 30, 2023	Apr. 30, 2022	Apr. 30, 2021
Restructuring Cost and Reserve [Line Items]
Restructuring charges, net		$ 1,525	$ 183	$ 5,848
Restructuring reserve		800
Employee Severance and Separation
Restructuring Cost and Reserve [Line Items]
Restructuring charges, net		$ 1,500
Manufacturing Plant Closure
Restructuring Cost and Reserve [Line Items]
Restructuring charges, net			$ 300	$ 4,400
Discontinued Operations, Disposed of by Sale | Humboldt Facility | Facility Closing
Restructuring Cost and Reserve [Line Items]
Gain (Loss) on Disposition of Business	$ 2,300