Accounts and Income Taxes Payable and Accrued Liabilities - Accrued Liabilities (Detail) - USD ($)	Mar. 31, 2018	Mar. 31, 2017
Payables And Accruals [Abstract]
Payroll, payroll taxes and employee benefits	$ 15,100,000	$ 14,465,000
Customer deposits	35,496,000	32,471,000
Accrued professional service fees	5,782,000	4,551,000
Self-insurance accruals	3,627,000	2,835,000
Deferred revenue	15,316,000	10,096,000
Accrued rent	6,147,000	5,774,000
Other	3,068,000	3,276,000
Total accrued liabilities	$ 84,536,000	$ 73,468,000