Leases - Lease Cost (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Lease costs:
Operating lease cost	$ 724	$ 655	$ 1,447	$ 1,380
Finance lease cost:
Depreciation expense	5	0	10	2
Interest on lease liabilities	1	2	2	4
Total finance lease cost	$ 6	$ 2	$ 12	$ 6