Segment Information - Disaggregation of Revenue By Geographical Region (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Segment Reporting Information [Line Items]
Revenues, net	$ 165,871	$ 184,063
Domestic
Segment Reporting Information [Line Items]
Revenues, net	164,134	181,015
Foreign
Segment Reporting Information [Line Items]
Revenues, net	$ 1,737	$ 3,048
Geographic Concentration Risk | Net Revenue
Segment Reporting Information [Line Items]
Concentration risk percentage	100.00%	100.00%
Geographic Concentration Risk | Net Revenue | Domestic
Segment Reporting Information [Line Items]
Concentration risk percentage	99.00%	98.30%
Geographic Concentration Risk | Net Revenue | Foreign
Segment Reporting Information [Line Items]
Concentration risk percentage	1.00%	1.70%