Goodwill and Intangible Assets - Intangible Assets (Detail) - USD ($) $ in Thousands	12 Months Ended
	Apr. 30, 2023	Apr. 30, 2022
Intangible Assets [Line Items]
Gross	$ 278,451	$ 230,051
Accumulated Amortization	(163,905)	(140,171)
Net	114,546	89,880
Exchange rate fluctuations	(120)	(110)
Amortized intangible assets, net	114,426	89,770
Infinity Consulting Solutions
Intangible Assets [Line Items]
Intangible asset addition	16,400
Salo
Intangible Assets [Line Items]
Intangible asset addition	32,000
Lucas Group
Intangible Assets [Line Items]
Intangible asset addition		11,600
Patina Solutions Group
Intangible Assets [Line Items]
Intangible asset addition		5,700
Customer lists
Intangible Assets [Line Items]
Gross	192,099	146,799
Accumulated Amortization	(104,429)	(89,024)
Net	87,670	57,775
Intellectual property
Intangible Assets [Line Items]
Gross	69,100	69,100
Accumulated Amortization	(47,187)	(40,720)
Net	21,913	28,380
Proprietary databases
Intangible Assets [Line Items]
Gross	4,256	4,256
Accumulated Amortization	(4,256)	(4,256)
Net	0	0
Non-compete agreements
Intangible Assets [Line Items]
Gross	910	910
Accumulated Amortization	(910)	(910)
Net	0	0
Trademarks
Intangible Assets [Line Items]
Gross	12,086	8,986
Accumulated Amortization	(7,123)	(5,261)
Net	$ 4,963	$ 3,725