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Equity Incentive Plans (Tables) | 12 Months Ended
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Dec. 31, 2021
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |
Schedule of Fair Value of Stock Option Grants Valuation Assumptions by Block-Scholes Option Pricing Model | The fair value of stock option grants is set forth below and was determined using the Black-Scholes option pricing model with the following assumptions:
|  | Year Ended December 31,
|  | 2021 |  | 2020 |  | 2019
Fair value of common stock |  | $31.12-$48.05 |  | $23.49-$34.07 |  | $20.07-$44.95
Expected term (in years) |  | 6 |  | 6 |  | 6
Risk-free interest rate |  | 0.45%-1.62% |  | 0.36%-0.83% |  | 1.71%-2.49%
Expected volatility |  | 65%-67% |  | 64%-68% |  | 64%-67%
Expected dividend yield |  | — |  | — |  | —
Schedule of Stock Option Activity | A summary of stock option activities during 2021, 2020 and 2019 is as follows:
|  | Number of Options Outstanding |  |  | Weighted Average Exercise Price |  |  | Weighted Average Grant Date Fair Value per Option |  |  | Aggregate Intrinsic Value Exercised (in thousands) |
Outstanding at December 31, 2018 |  |  | 820,186 |  |  | $ | 8.44 |  |  |  |  |  |  |
Granted |  |  | 138,200 |  |  | $ | 35.76 |  |  | $ | 21.86 |  |  |  |
Exercised |  |  | (307,365 | ) |  | $ | 1.47 |  |  |  |  |  | $ | 12,117 |
Canceled |  |  | (33,528 | ) |  | $ | 24.80 |  |  |  |  |  |  |
Outstanding at December 31, 2019 |  |  | 617,493 |  |  | $ | 17.13 |  |  |  |  |  |  |
Granted |  |  | 347,095 |  |  | $ | 32.14 |  |  | $ | 19.15 |  |  |  |
Exercised |  |  | (96,456 | ) |  | $ | 3.25 |  |  |  |  |  | $ | 2,257 |
Canceled |  |  | (54,890 | ) |  | $ | 26.07 |  |  |  |  |  |  |
Outstanding at December 31, 2020 |  |  | 813,242 |  |  | $ | 24.58 |  |  |  |  |  |  |
Granted |  |  | 111,489 |  |  | $ | 39.00 |  |  | $ | 23.32 |  |  |  |
Exercised |  |  | (97,702 | ) |  | $ | 9.20 |  |  |  |  |  | $ | 3,064 |
Canceled |  |  | (43,101 | ) |  | $ | 35.84 |  |  |  |  |  |  |
Outstanding at December 31, 2021 |  |  | 783,928 |  |  | $ | 28.00 |  |  |  |  |  |  |
Schedule of Additional Information for Stock Options | Additional information for stock options at December 31, 2021 were as follows:
| Number of Options |  |  | Weighted Average Exercise Price |  |  | Aggregate Intrinsic Value (in thousands) |  |  | Weighted Average Remaining Contractual term (in years) |
Outstanding at December 31, 2021 |  | 783,928 |  |  |  | 28.00 |  |  | $ | 4,524 |  |  |  | 7.30 |
Exercisable at December 31, 2021 |  | 453,000 |  |  |  | 23.17 |  |  | $ | 4,362 |  |  |  | 6.37 |
Schedule of Unvested Restricted Stock Units Awards Activity | The following table summarizes the activity of RSU awards:
|  | Number of RSUs |  |  | Weighted Average Grant Date Fair Value per RSU |  |  | Aggregate Fair Value of RSUs Vested (in thousands) |
Unvested RSUs at December 31, 2018 |  |  | 110,764 |  |  | $ | 19.58 |  |  |  |
Granted |  |  | 62,382 |  |  | $ | 44.05 |  |  |  |
Vested |  |  | (58,150 | ) |  | $ | 24.75 |  |  | $ | 2,610 |
Unvested RSUs at December 31, 2019 |  |  | 114,996 |  |  | $ | 30.24 |  |  |  |
Granted |  |  | 91,759 |  |  | $ | 31.75 |  |  |  |
Vested |  |  | (54,970 | ) |  | $ | 32.12 |  |  | $ | 1,766 |
Forfeited |  |  | (10,277 | ) |  | $ | 41.50 |  |  |  |
Unvested RSUs at December 31, 2020 |  |  | 141,508 |  |  | $ | 29.67 |  |  |  |
Granted |  |  | 84,035 |  |  | $ | 37.86 |  |  |  |
Vested |  |  | (80,972 | ) |  | $ | 29.22 |  |  | $ | 3,078 |
Forfeited |  |  | (15,761 | ) |  | $ | 31.38 |  |  |  |
Unvested RSUs at December 31, 2021 |  |  | 128,810 |  |  | $ | 35.09 |  |  |  |
Schedule of Stock-Based Compensation Expense Recorded in Consolidated Statements of Operations | Total stock-based compensation expense is recorded in the consolidated statements of operations and was allocated as follows (in thousands):
| Year Ended December 31, |
| 2021 |  |  | 2020 |  |  | 2019 |
Cost of revenues | $ | 1,567 |  |  | $ | 1,093 |  |  | $ | 670 |
Sales and marketing |  | 1,612 |  |  |  | 1,268 |  |  |  | 955 |
Research and development |  | 734 |  |  |  | 580 |  |  |  | 365 |
General and administrative |  | 1,959 |  |  |  | 1,521 |  |  |  | 1,067 |
Total | $ | 5,872 |  |  | $ | 4,462 |  |  | $ | 3,057 |
2017 Equity Incentive Plan |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |
Schedule of Activity of Shares Available for Grant | The following table summarizes the activity of shares available for grant under the 2017 Equity Incentive Plan:
Shares available for grant at December 31, 2020 |  |  | 1,814,379 |
Increase in accordance with the evergreen provision |  |  | — |
Options issued during the year |  |  | (111,489 | )
Canceled during the year |  |  | 43,101 |
RSUs granted |  |  | (84,035 | )
Shares available for grant at December 31, 2021 |  |  | 1,661,956 |
2017 Employee Stock Purchase Plan |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |
Schedule of Activity of Shares Available for Grant | The following table summarizes the activity of shares available under the 2017 ESPP:
Shares available for grant at December 31, 2020 |  |  | 429,521 |
Increase in accordance with the evergreen provision |  |  | — |
Issued during the year |  |  | (30,193 | )
Shares available for grant at December 31, 2021 |  |  | 399,328 |

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