Property and Equipment - Property and Equipment, Net (Detail) - USD ($)	Mar. 31, 2016	Mar. 31, 2015
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 184,004,000	$ 175,011,000
Less: accumulated depreciation and amortization	(130,736,000)	(118,712,000)
Property and equipment, net	53,268,000	56,299,000
Computer Software Property and Equipment [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	114,883,000	101,955,000
Office Equipment And Computers [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	60,061,000	64,462,000
Leasehold Improvements [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 9,060,000	$ 8,594,000