Segments - Reconciliation of Net Income to Adjusted EBITDA (Details) - USD ($) $ in Thousands	3 Months Ended
	Jul. 31, 2021	Jul. 31, 2020
Segment Reporting [Abstract]
Net income	$ 61,202	$ 27,219
Interest expense	13,657	14,081
Interest income	0	(37)
Provision for income taxes	19,971	9,604
Depreciation expense	12,925	12,827
Amortization expense	14,789	14,270
Stock appreciation rights	892	792
Redeemable noncontrolling interests	310	252
Equity-based compensation	1,958	1,605
Severance and other permitted costs	147	1,947
Transaction costs (acquisitions and other)	575	100
(Gain) loss on disposal and impairment of assets	(78)	394
Effects of fair value adjustments to inventory	1,731	0
Adjusted EBITDA	$ 128,079	$ 83,054