Equity Incentive Plans and Stock-Based Compensation - Stock-Based Compensation Expense - Additional Information (Details) $ in Millions	9 Months Ended
Sep. 30, 2020 USD ($)
Restricted Stock Awards
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Unrecognized compensation cost	$ 0.3
Unrecognized compensation expense, weighted average period	1 year 5 months 15 days
Stock Options
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Unrecognized compensation expense, weighted average period	2 years 8 months 4 days
Unrecognized compensation cost	$ 11.4

Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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-Publisher FASB
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