Stockholder's Equity - Narrative (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020
Inducement Equity Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)	56,500
Inducement Equity Incentive Plan \| Common Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)	56,500
2017 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation costs	$ 1,000
Granted (in shares)	163,285	191,500
Employee Stock Option \| Inducement Equity Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense	$ 200
Compensation cost not yet recognized	400
Employee Stock Option \| 2017 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense	1,700	$ 2,100
Employee Stock Option \| Pre-2017 Non-Qualified Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense	0	1,235
Restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense	800	$ 200
Compensation cost not yet recognized	$ 500
Granted (in shares)	76,268,000	49,600,000
Restricted stock units \| Tranche One
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage	25.00%
Restricted stock units \| Tranche Two
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage	25.00%
Restricted stock units \| Inducement Equity Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense	$ 100
Compensation cost not yet recognized	$ 1,200
Restricted Stock \| Inducement Equity Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)	49,800

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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