Leases - Supplemental Balance Sheet (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Leases [Abstract]
Property and equipment	$ 482	$ 572
Accumulated depreciation	$ (394)	$ (229)
Finance lease, right-of-use asset, statement of financial position [Extensible List]	Property and equipment, net	Property and equipment, net
Property and equipment, net	$ 88	$ 343
Finance lease, liability, current, statement of financial position [Extensible List]	Accruals and other current liabilities	Accruals and other current liabilities
Accruals and other current liabilities	$ 146	$ 197
Finance lease, liability, noncurrent, statement of financial position [Extensible List]	Other liabilities	Other liabilities
Other liabilities	$ 0	$ 99
Total financing lease liabilities	$ 146	$ 296