Property and Equipment - Property and Equipment, Net (Detail) - USD ($)	Mar. 31, 2020	Mar. 31, 2019
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 243,188,000	$ 240,273,000
Less: accumulated depreciation and amortization	(167,288,000)	(178,293,000)
Property and equipment, net	75,900,000	61,980,000
Computer Software [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	150,780,000	152,885,000
Office Equipment And Computers [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	66,398,000	68,006,000
Land, Building And Improvements [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	11,048,000	5,843,000
Leasehold Improvements [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 14,962,000	$ 13,539,000