Property and Equipment - Components of Property and Equipment (Detail) - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 363,145	$ 369,921
Less accumulated depreciation	(93,860)	(96,700)
Total property and equipment, net	269,285	273,221
Computer Equipment [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	26,666	36,373
Land [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	89,130	89,130
Building [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	197,020	195,372
Furniture and Fixtures [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	10,485	10,348
Leasehold Improvements [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	8,428	7,748
Software [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 31,416	$ 30,950