Operating Leases - Components of Lease Costs (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Leases [Abstract]
Operating lease costs	$ 1,760	$ 1,841
Short-term lease costs	437	479
Variable lease costs	493	514
Lease costs	$ 2,690	$ 2,834