Schedule of Property and Equipment (Detail) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Property, Plant and Equipment [Line Items]
Property and equipment	$ 227,056	$ 217,922
Less accumulated depreciation and amortization	120,580	112,146
Property and equipment, net	106,476	105,776
Office Building
Property, Plant and Equipment [Line Items]
Property and equipment	54,125	55,293
Computer Equipment and Software
Property, Plant and Equipment [Line Items]
Property and equipment	55,614	54,951
Furniture, Fixtures And Other Equipment
Property, Plant and Equipment [Line Items]
Property and equipment	72,264	71,542
Vehicles
Property, Plant and Equipment [Line Items]
Property and equipment	2,058	2,237
Leasehold Improvements
Property, Plant and Equipment [Line Items]
Property and equipment	7,536	8,058
Leasehold Land
Property, Plant and Equipment [Line Items]
Property and equipment	4,680	4,783
Residential Property
Property, Plant and Equipment [Line Items]
Property and equipment	1,602	1,637
Capital Advances / Work In Progress
Property, Plant and Equipment [Line Items]
Property and equipment	$ 29,177	$ 19,421