Accounts and Income Taxes Payable and Accrued Liabilities - Accrued Liabilities (Detail) - USD ($)	Sep. 30, 2022	Mar. 31, 2022
Payables and Accruals [Abstract]
Payroll, payroll taxes and employee benefits	$ 31,879,000	$ 36,066,000
Customer deposits	75,770,000	69,781,000
Accrued professional service fees	7,494,000	8,073,000
Self-insurance accruals	2,872,000	2,798,000
Deferred revenue	27,051,000	25,796,000
Operating lease liabilities	11,495,000	13,348,000
Other	1,921,000	1,077,000
Total accrued liabilities	$ 158,482,000	$ 156,939,000