Accounts and Income Taxes Payable and Accrued Liabilities - Accrued Liabilities (Detail) - USD ($)	Dec. 31, 2021	Mar. 31, 2021
Payables and Accruals [Abstract]
Payroll, payroll taxes and employee benefits	$ 38,570,000	$ 43,998,000
Customer deposits	70,163,000	56,498,000
Accrued professional service fees	7,590,000	7,016,000
Self-insurance accruals	2,968,000	3,704,000
Deferred revenue	22,820,000	22,514,000
Operating lease liabilities	13,807,000	12,765,000
Other	2,273,000	2,391,000
Total accrued liabilities	$ 158,191,000	$ 148,886,000