Property and Equipment - Schedule (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 537,501	$ 522,217
Accumulated depreciation	276,770	251,170
Net property and equipment	260,731	271,047
Land and improvements
Property, Plant and Equipment [Line Items]
Property and equipment, gross	59,176	59,176
Buildings and improvements
Property, Plant and Equipment [Line Items]
Property and equipment, gross	148,392	141,510
Equipment
Property, Plant and Equipment [Line Items]
Property and equipment, gross	315,352	303,867
Computer software
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 14,581	$ 17,664