Fee Revenue - Schedule of Disaggregation of Fee Revenue by Industry (Detail) - USD ($) $ in Thousands	12 Months Ended
	Apr. 30, 2023	Apr. 30, 2022	Apr. 30, 2021
Disaggregation Of Revenue [Line Items]
Fee revenue	$ 2,863,836	$ 2,643,455	$ 1,819,946
Industrial
Disaggregation Of Revenue [Line Items]
Fee revenue	$ 805,241	$ 688,902	$ 490,863
Fee revenue, percentage	28.40%	26.20%	27.10%
Life Sciences/Healthcare
Disaggregation Of Revenue [Line Items]
Fee revenue	$ 522,372	$ 501,463	$ 355,668
Fee revenue, percentage	18.40%	19.10%	19.70%
Financial Services
Disaggregation Of Revenue [Line Items]
Fee revenue	$ 494,299	$ 475,326	$ 331,976
Fee revenue, percentage	17.40%	18.10%	18.30%
Technology
Disaggregation Of Revenue [Line Items]
Fee revenue	$ 483,787	$ 456,498	$ 275,510
Fee revenue, percentage	17.10%	17.40%	15.20%
Consumer Goods
Disaggregation Of Revenue [Line Items]
Fee revenue	$ 386,409	$ 372,720	$ 239,457
Fee revenue, percentage	13.60%	14.20%	13.20%
Education/Non–Profit/General
Disaggregation Of Revenue [Line Items]
Fee revenue	$ 143,300	$ 131,809	$ 116,573
Fee revenue, percentage	5.10%	5.00%	6.50%
Fee Revenue
Disaggregation Of Revenue [Line Items]
Fee revenue	$ 2,835,408	$ 2,626,718	$ 1,810,047
Fee revenue, percentage	100.00%	100.00%	100.00%