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Stockholders' Equity - Additional Information (Details) $ / shares in Units, $ in Millions |  | 9 Months Ended |  |  |  |
--- | --- | --- | --- | --- | --- | ---
Sep. 02, 2021 day $ / shares shares | Sep. 30, 2021 USD ($) $ / shares shares | Sep. 30, 2020 USD ($) shares | Nov. 03, 2021 USD ($) $ / shares | Dec. 31, 2020 shares | Jul. 28, 2020 shares | May 16, 2012 shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |
Common stock authorized (in shares) |  | 75,000,000 |  |  |  |  |
Common stock par value (in usd per share) | $ / shares |  | $ 0.0001 |  |  |  |  |
Preferred stock authorized (in shares) |  | 25,000,000 |  |  |  |  |
Preferred stock par value (in usd per share) | $ / shares | $ 0.00001 | $ 0.0001 |  |  |  |  |
Options outstanding (in shares) |  | 0 |  |  | 0 |  |
Common stock outstanding (in shares) |  | 19,468,276 |  |  | 19,384,192 |  |
Preferred stock outstanding (in shares) |  | 0 |  |  | 0 |  |
Number of rights issued for each share of common stock outstanding (in shares) | 1 |  |  |  |  |  |
Number of Series A Junior Participating Preferred Stock shares attributable to each right (in shares) | 0.10 |  |  |  |  |  |
Exercise price of right (in usd per share) | $ / shares | $ 50.95 |  |  |  |  |  |
Acquiring person, percentage of ownership threshold | 10.00% |  |  |  |  |  |
Acquiring person, passive institutional investor, percentage of ownership threshold | 20.00% |  |  |  |  |  |
Number of business days following tender or exchange offer to trigger exercisability | day | 10 |  |  |  |  |  |
Issuance of common stock under the employee stock purchase plan (in shares) |  | 16,015 | 18,586 |  |  |  |
Issuance of common stock under the employee stock purchase plan | $ |  | $ 0.1 | $ 0.2 |  |  |  |
Subsequent Event |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |
Dividend rate (in usd per share) | $ / shares |  |  |  | $ 0.125 |  |  |
Dividends declared | $ |  |  |  | $ 2.4 |  |  |
Unvested RSUs, DSUs and Restricted Stock |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |
Equity instruments other than options, nonvested (in shares) |  | 1,103,851 |  |  | 636,722 |  |
Shares issued, weighted average grant date fair value (in usd per share) | $ / shares |  | $ 11.02 |  |  |  |  |
2012 Equity Plan |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |
Shares reserved for future issuance (in shares) |  |  |  |  |  |  | 2,194,986
Shares issued (in shares) |  | 169,944 |  |  |  |  |
2012 Equity Plan | Contingent RSUs |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |
Equity instruments other than options, nonvested (in shares) |  | 519,832 |  |  |  |  |
2012 Equity Plan | Restricted Stock and Restricted Stock Units (RSUs) |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |
Equity instruments other than options, nonvested (in shares) |  | 496,211 |  |  |  |  |
Compensation cost not yet recognized, share-based awards other than options | $ |  | $ 5.5 |  |  |  |  |
Weighted-average period over which cost is expected to be recognized |  | 1 year 8 months 12 days |  |  |  |  |
2012 Equity Plan | Unvested RSUs, DSUs and Restricted Stock |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |
Shares issued (in shares) |  | 169,944 |  |  |  |  |
2012 Equity Plan | Share-based Payment Arrangement |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |
Shares issued, weighted average grant date fair value (in usd per share) | $ / shares |  | $ 10.87 |  |  |  |  |
2020 Equity Plan |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |
Shares reserved for future issuance (in shares) |  |  |  |  |  | 1,699,950 |
2020 Equity Plan | Restricted Stock |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |
Vesting period |  | 1 year |  |  |  |  |
2020 Equity Plan | Contingent RSUs |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |
Vesting period |  | 3 years |  |  |  |  |
2020 Equity Plan | Non-contingent RSUs |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |
Vesting period |  | 3 years |  |  |  |  |
ESPP |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |
Shares reserved for future issuance (in shares) |  | 250,000 |  |  |  |  |
Award required holding period |  | 2 years |  |  |  |  |
ESPP | Maximum |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |
Offering period, maximum |  | 6 months |  |  |  |  |

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