Income Taxes - Carryforwards, unrecognized benefits (Details) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Income Taxes [Line Items]
Increase in valuation allowance			$ 32,000	$ 28,500	$ 900
Operating loss carryforwards foreign	$ 2,800		2,800
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Unrecognized tax benefits, beginning balance			1,003	670	540
Additions based on tax positions related to the current year			230	161	130
Additions based on tax positions related to prior years			39	172	0
Unrecognized tax benefits, ending balance	1,272	$ 1,003	1,272	$ 1,003	670
Unrecognized tax benefits, uncertainty in income taxes	1,400		1,400
Accrued liability, CARES Act					$ 3,800
Payments for deferred payroll tax, CARES Act	1,900	$ 1,900
Domestic Tax Authority
Income Taxes [Line Items]
Operating loss carryforwards	141,900		141,900
Operating loss carryforwards subject to expiration	87,700		87,700
Operating loss carryforwards not subject to expiration	54,200		54,200
Domestic Tax Authority | Research Tax Credit Carryforward
Income Taxes [Line Items]
Tax credit carryforward, amount	8,000		8,000
Foreign Tax Authority
Income Taxes [Line Items]
Operating loss carryforwards	59,700		59,700
Tax credit carryforward, amount	1,900		1,900
State and Local Jurisdiction
Income Taxes [Line Items]
Operating loss carryforwards	93,300		93,300
State and Local Jurisdiction | Research Tax Credit Carryforward
Income Taxes [Line Items]
Tax credit carryforward, amount	$ 3,500		$ 3,500