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Stock-Based Compensation (Tables) | 6 Months Ended
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Jun. 30, 2024
Share-Based Payment Arrangement [Abstract] |
Share-Based Payment Arrangement, Option, Activity | The following table summarizes stock option activity during the six months ended June 30, 2024:
| Stock Options |  | Weighted- Average Exercise Price
Options outstanding at December 31, 2023 | 371,313 |  | $ | 59.92 |
Granted | 139,215 |  | 33.41 |
Exercised | — |  | —
Forfeited | (29,729) |  | 76.23 |
Expired | (5,094) |  | 67.78 |
Options outstanding at June 30, 2024 | 475,705 |  | $ | 51.06 |
Exercisable at June 30, 2024 | 190,014 |  | $ | 70.24 |
Schedule of Share-Based Payment Award, Stock Options, Valuation Assumptions | The following table provides the assumptions used in the Black-Scholes pricing model valuation of options during the six months ended June 30, 2024 and 2023:
| Six Months Ended June 30,
| 2024 |  | 2023
Risk-free interest rate | 4.28% - 4.30% |  | 3.90% - 4.55%
Expected life (years) | 6.25 |  | 2.00 - 6.25
Expected volatility | 50.62% - 50.72% |  | 49.23% - 55.92%
Expected dividend yield | 0% |  | 0%
Share-Based Payment Arrangement, Restricted Stock and Restricted Stock Unit, Activity | The following table summarizes restricted stock activity during the six months ended June 30, 2024:
| Restricted Stock |  | Weighted- Average Grant Date Fair Value Per Share
Restricted stock at December 31, 2023 | 653,465 |  | $ | 45.89 |
Granted | 336,785 |  | 33.02 |
Restrictions lapsed | (191,950) |  | 54.48 |
Forfeited | (26,289) |  | 42.36 |
Restricted stock at June 30, 2024 | 772,011 |  | $ | 38.26 |
Schedule of Nonvested Performance-Based Units Activity | The following table summarizes performance stock activity during the six months ended June 30, 2024:
| Performance Stock |  | Weighted- Average Grant Date Fair Value Per Share
Performance stock at December 31, 2023 | 107,097 |  | $ | 74.08 |
Granted | 79,436 |  | 48.20 |
Restrictions lapsed | — |  | —
Performance change | (2,772) |  | 227.14 |
Forfeited | — |  |
Performance stock at June 30, 2024 | 183,761 |  | $ | 60.58 |
Schedule of Share-based Payment Award, Awards Other Than Stock Options, Valuation Assumptions | The following table provides the assumptions used in the Monte Carlo pricing model valuation of PSUs during the six months ended June 30, 2024 and 2023:
| Six Months Ended June 30,
| 2024 |  | 2023
Risk-free interest rate | 4.37% |  | 4.35%
Expected life (years) | 2.88 |  | 2.88
Expected volatility | 51.40% |  | 58.00%
Expected dividend yield | 0% |  | 0%
Schedule of Share-Based Payment Award, Employee Stock Purchase Plan, Valuation Assumptions | The following table presents the assumptions used to estimate the fair value of the ESPP during the six months ended June 30, 2024 and 2023:
| Six Months Ended June 30,
| 2024 |  | 2023
Risk-free interest rate | 5.07% - 5.16% |  | 4.60% - 4.82%
Expected life (months) | 6.00 |  | 6.00
Expected volatility | 30.97% - 47.92% |  | 47.38% - 67.84%
Expected dividend yield | 0% |  | 0%

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- Definition Tabular disclosure of the significant assumptions used during the year to estimate the fair value of employee stock purchase plans, including, but not limited to: (a) expected term, (b) expected volatility of the entity's shares, (c) expected dividends, (d) risk-free rate(s), and (e) discount for post-vesting restrictions. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 718 -SubTopic 10 -Subparagraph (f)(2) -Name Accounting Standards Codification -Paragraph 2 -Section 50 -Publisher FASB -URI https://asc.fasb.org/1943274/2147480429/718-10-50-2 + Details
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- Definition Tabular disclosure of the significant assumptions used during the year to estimate the fair value of stock options, including, but not limited to: (a) expected term of share options and similar instruments, (b) expected volatility of the entity's shares, (c) expected dividends, (d) risk-free rate(s), and (e) discount for post-vesting restrictions. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 718 -SubTopic 10 -Subparagraph (f)(2) -Name Accounting Standards Codification -Paragraph 2 -Section 50 -Publisher FASB -URI https://asc.fasb.org/1943274/2147480429/718-10-50-2 + Details
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