Fee Revenue - Schedule of Disaggregation of Fee Revenue by Industry (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Jan. 31, 2022	Jan. 31, 2021	Jan. 31, 2022	Jan. 31, 2021
Disaggregation Of Revenue [Line Items]
Fee Revenue	$ 684,956	$ 477,880	$ 1,916,452	$ 1,262,552
Industrial
Disaggregation Of Revenue [Line Items]
Fee Revenue	$ 181,016	$ 131,959	$ 500,078	$ 346,650
Fee Revenue, Percentage	26.60%	27.80%	26.20%	27.60%
Life Sciences/Healthcare
Disaggregation Of Revenue [Line Items]
Fee Revenue	$ 126,840	$ 92,588	$ 370,009	$ 241,451
Fee Revenue, Percentage	18.60%	19.50%	19.40%	19.30%
Financial Services
Disaggregation Of Revenue [Line Items]
Fee Revenue	$ 121,459	$ 84,078	$ 341,099	$ 232,723
Fee Revenue, Percentage	17.80%	17.70%	17.90%	18.50%
Technology
Disaggregation Of Revenue [Line Items]
Fee Revenue	$ 124,903	$ 74,774	$ 323,504	$ 188,789
Fee Revenue, Percentage	18.40%	15.70%	17.00%	15.00%
Consumer Goods
Disaggregation Of Revenue [Line Items]
Fee Revenue	$ 97,210	$ 63,325	$ 271,233	$ 168,840
Fee Revenue, Percentage	14.30%	13.30%	14.20%	13.50%
Education/Non-Profit/General
Disaggregation Of Revenue [Line Items]
Fee Revenue	$ 29,313	$ 28,636	$ 99,656	$ 76,443
Fee Revenue, Percentage	4.30%	6.00%	5.30%	6.10%
Fee Revenue
Disaggregation Of Revenue [Line Items]
Fee Revenue	$ 680,741	$ 475,360	$ 1,905,579	$ 1,254,896
Fee Revenue, Percentage	100.00%	100.00%	100.00%	100.00%