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Equity Incentive Plans - Additional Information (Details) | 1 Months Ended | 12 Months Ended
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May 31, 2017 shares | Dec. 31, 2021 USD ($) Participant $ / shares shares | Dec. 31, 2020 $ / shares shares | Dec. 31, 2019 $ / shares shares | Dec. 31, 2017
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |
Unvested options resulting from early exercises |  | 0 | 0 | 0 |
Options to Purchase Common Stock |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |
Total unrecognized stock-based compensation cost related to unvested stock options | $ |  | $ 6,500,000 |  |  |
Total unrecognized stock-based compensation cost related to unvested stock options, recognized ratably over a weighted-average period |  | 2 years 7 months 6 days |  |  |
Income tax benefits from stock-based compensation | $ |  | $ 0 |  |  |
Restricted Stock Unit |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |
Total unrecognized stock-based compensation cost related to unvested stock options, recognized ratably over a weighted-average period |  | 2 years 4 months 24 days |  |  |
Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Grants In Period |  | 84,035 | 91,759 | 62,382 |
Grant Date Fair Value, Granted | $ / shares |  | $ 37.86 | $ 31.75 | $ 44.05 |
Total unrecognized stock-based compensation cost related RSUs | $ |  | $ 3,800,000 |  |  |
Restricted Stock Unit | Executive Management |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |
Vesting period |  | 4 years |  |  |
2005 Plan |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |
Number of shares available for future grant | 0 |  |  |  |
2017 Equity Incentive Plan |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |
Number of shares available for future grant |  | 1,661,956 | 1,814,379 |  |
Shares of common stock reserved for issuance, automatic annual increase initiation period | --01-01 |  |  |  |
Percentage of number of shares of common stock outstanding |  |  |  |  | 5.00%
Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Grants In Period |  | 84,035 |  |  |
Incentive Stock Options |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |
Ownership percentage, minimum |  | 10.00% |  |  |
Incentive Stock Options | Minimum |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |
Percentage of fair value of common stock granted to employees |  | 110.00% |  |  |
2005 Plan and 2017 Plan |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |
Vesting period |  | 4 years |  |  |
2005 Plan and 2017 Plan | Maximum |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |
Expiration period |  | 10 years |  |  |
2017 Employee Stock Purchase Plan |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |
Number of shares available for future grant |  | 399,328 | 429,521 |  |
Percentage of number of shares of common stock outstanding |  | 2.00% |  |  |
Percentage of fair market value of common stock at beginning and end of offering period | 15.00% |  |  |  |
Purchase of common stock under ESPP, Description |  | The 2017 ESPP permits the maximum discounted purchase price permitted under U.S. tax rules, including a “lookback”, which allows eligible employees to purchase shares of the Company’s common stock at a 15% discount to the lesser of the fair market value of common stock at the beginning and end of the offering period. |  |  |
Initial offering period in length |  | 24 months |  |  |
Number of participant have the right to purchase shares of common stock | Participant |  | 0 |  |  |
Fair Market Value Of Common Stock | $ |  | $ 25,000 |  |  |
Periodic increment of common stock reserved for future issuance |  | 150,000 |  |  |

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