Segments - Reconciliation of Net Income to Adjusted EBITDA (Details) - USD ($) $ in Thousands	3 Months Ended				6 Months Ended
	Oct. 31, 2021	Jul. 31, 2021	Oct. 31, 2020	Jul. 31, 2020	Oct. 31, 2021	Oct. 31, 2020
Segment Reporting [Abstract]
Net income	$ 74,361	$ 61,202	$ 28,469	$ 27,219	$ 135,563	$ 55,688
Interest expense	14,744		13,525		28,401	27,606
Interest income	(27)		(14)		(27)	(51)
Provision for income taxes	23,769		8,277		43,740	17,881
Depreciation expense	13,703		12,710		26,628	25,537
Amortization expense	15,700		14,535		30,489	28,805
Stock appreciation rights	983		314		1,875	1,106
Redeemable noncontrolling interests	593		186		903	438
Equity-based compensation	3,215		3,252		5,173	4,857
Severance and other permitted costs	249		762		396	2,709
Transaction costs (acquisitions and other)	2,393		25		2,968	125
(Gain) loss on disposal and impairment of assets	(144)		481		(222)	875
Effects of fair value adjustments to inventory	0		0		1,731	0
Adjusted EBITDA	$ 149,539		$ 82,522		$ 277,618	$ 165,576