Leases - Condensed Consolidated Balance Sheets (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Assets
Operating lease assets	$ 1,692	$ 1,959
Finance lease assets	480	721
Total lease assets	$ 2,172	$ 2,680
Finance Lease, Right-of-Use Asset, Statement of Financial Position [Extensible Enumeration]	Property and equipment, net	Property and equipment, net
Current
Operating lease liabilities	$ 546	$ 434
Finance lease liabilities	309	321
Non-current
Operating lease liabilities	1,082	1,403
Finance lease liabilities	192	418
Total lease liabilities	$ 2,129	$ 2,576
Finance Lease, Liability, Current, Statement of Financial Position [Extensible Enumeration]	Other accrued liabilities	Other accrued liabilities