Lease Agreements - Lease related expenses (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Finance lease expense:
Amortization of finance lease assets	$ 1,029	$ 1,046
Interest on finance lease liabilities	405	424
Operating lease expense	8,208	8,551
Variable lease expense	712	612
Short-term lease expense	27	34
Sublease Income	(493)	(744)
Total lease expense	$ 9,888	$ 9,923