Lease Agreements - Lease-related assets and liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
ASSETS
Operating lease assets	$ 28,083	$ 29,423
Finance lease assets	9,525	10,293
Total lease assets	37,608	39,716
Current
Operating	6,585	6,537
Finance	676	596
Noncurrent
Operating	21,530	22,760
Finance	7,727	8,208
Total liabilities	$ 36,518	$ 38,101
Weighted average remaining lease term (years)
Operating leases	5 years 1 month 6 days	5 years 6 months
Finance leases	9 years 9 months 18 days	10 years 10 months 24 days
Weighted average discount rate
Operating leases	5.10%	5.20%
Finance leases	4.70%	4.70%