Leases - Operating Lease Costs (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Leases [Abstract]
Operating lease cost	$ 1,425	$ 1,425	$ 2,850	$ 2,768
Variable lease cost	272	298	349	588
Total operating lease costs	$ 1,697	$ 1,723	$ 3,199	$ 3,356