Leases - Supplemental Balance sheet information (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Supplemental balance sheet information related to leases
Operating lease - right of use asset	$ 21,441	$ 22,557
Other current liabilities	4,326	3,822
Operating lease liabilities	17,434	18,981
Total operating lease liabilities	$ 21,760	$ 22,803
Weighted Average Remaining Lease Term - Operating leases	67 months	78 months
Weighted Average Discount Rate - Operating leases	5.16%	5.32%