Accounts and Taxes Payable and Accrued Liabilities - Accrued Liabilities (Detail) - USD ($)	Jun. 30, 2019	Mar. 31, 2019
Payables And Accruals [Abstract]
Payroll, payroll taxes and employee benefits	$ 20,338,000	$ 23,647,000
Customer deposits	43,667,000	45,268,000
Accrued professional service fees	6,282,000	8,377,000
Self-insurance accruals	3,560,000	3,523,000
Deferred revenue	16,643,000	16,900,000
Operating lease liabilities	15,185,000	5,708,000
Other	1,926,000	2,018,000
Total accrued liabilities	$ 107,601,000	$ 105,441,000