Segment Information - Narrative (Details) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2019 USD ($)	Sep. 30, 2019 USD ($)	Jun. 30, 2019 USD ($)	Mar. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)	Sep. 30, 2018 USD ($)	Jun. 30, 2018 USD ($)	Mar. 31, 2018 USD ($)	Dec. 31, 2019 USD ($) segment	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)
Segment Reporting [Abstract]
Number of operating segments | segment									2
Number of reportable segments (in segment) | segment									2
Segment Reporting Information [Line Items]
Revenues | $	$ 162,257	$ 176,244	$ 178,057	$ 165,871	$ 153,386	$ 165,625	$ 190,944	$ 184,063	$ 682,429	$ 694,018	$ 841,045
Outside the United States
Segment Reporting Information [Line Items]
Revenues | $									$ 13,200	$ 16,400	$ 25,500