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Debt (Details) - USD ($) $ in Thousands	12 Months Ended
Debt (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Apr. 30, 2020	Apr. 21, 2020
Debt Instrument [Line Items]
Unsecured loan				$ 900
Loss on debt extinguishment	$ 0	$ 0	$ (3,495)
Cares Act PPP Loan
Debt Instrument [Line Items]
Loss on debt extinguishment	$ 900
Silicon Valley Bank \| Cares Act PPP Loan \| Commercial paper
Debt Instrument [Line Items]
Unsecured loan		300
Unsecured loan term (months)					24 months
Unsecured loan interest rate (percent)					1.00%
Short-term debt		$ 600