Stockholders' Equity - The 2017 Plan, Additional Information (Details) - USD ($) $ / shares in Units, $ in Thousands	9 Months Ended
Sep. 30, 2020	Sep. 30, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock based compensation expense	$ 126
2017 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options granted (in shares)	191,500
Options granted, exercise price (in dollars per share)	$ 12.12
Expiration period	10 years
Vesting percentage	100.00%
Fair value of option granted	$ 1,800
Compensation not yet recognized	$ 1,800
2017 Plan \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options granted, exercise price (in dollars per share)	$ 8.79
2017 Plan \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options granted, exercise price (in dollars per share)	$ 13.60
2017 Plan \| Options to purchase common stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expiration period	10 years
Stock based compensation expense	$ 1,600	$ 2,400
Tranche One
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage	25.00%
Tranche One \| 2017 Plan \| Options to purchase common stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage	25.00%
Tranche Two
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage	25.00%
Tranche Two \| 2017 Plan \| Options to purchase common stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage	2.0833%
Tranche Three \| 2017 Plan \| Options to purchase common stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage	2.0833%
Tranche Four \| 2017 Plan \| Options to purchase common stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage	2.0833%

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

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