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Share-Based Compensation - Narrative (Details) $ / shares in Units, $ in Millions | 12 Months Ended
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Dec. 31, 2023 USD ($) plan $ / shares shares | Dec. 31, 2022 USD ($) $ / shares shares | Dec. 31, 2021 USD ($) $ / shares shares
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items] |  |  |
Number of plans | plan | 5 |  |
Total share-based compensation expense | $ 11.6 | $ 7.8 | $ 9.5
Total excess tax benefit recognized for share-based compensation arrangements | $ 0.1 | $ 0.3 | $ 0.7
Weighted-average grant date fair value of stock options granted (in dollars per share) | $ / shares | $ 24.21 | $ 23.45 | $ 22.01
Total intrinsic value of stock options exercised | $ 5.9 | $ 0.4 | $ 3.9
Aggregate intrinsic value of options outstanding | 14.3 |  |
Aggregate intrinsic value of options exercisable | $ 12.5 |  |
Weighted-average remaining contractual life for options outstanding | 5 years 1 month 6 days |  |
Weighted-average remaining contractual life for options exercisable | 4 years 3 months 18 days |  |
Total share-based liabilities | $ 0.4 | 0.3 |
Option |  |  |
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items] |  |  |
New stock option awards granted vest period | 3 years |  |
Contractual term | 10 years |  |
Unrecognized compensation cost for non-vested options | $ 1.5 |  |
Weighted-average period | 1 year 3 months 18 days |  |
Restricted Stock |  |  |
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items] |  |  |
New stock option awards granted vest period | 3 years |  |
Unrecognized compensation cost for non-vested options | $ 1.5 |  |
Weighted-average period | 1 year 8 months 12 days |  |
Required service period following grant date | 6 months |  |
Vesting rights, required advance notice for resignation, period | 6 months |  |
Total fair value of restricted shares vested | $ 0.4 | $ 1.7 | $ 1.2
Vested (in shares) | shares | 5,667 |  |
Restricted Stock | Year One |  |  |
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items] |  |  |
Vesting percentage of awards granted | 33.33% |  |
Restricted Stock | Year Two |  |  |
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items] |  |  |
Vesting percentage of awards granted | 33.33% |  |
Restricted Stock | Year Three |  |  |
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items] |  |  |
Vesting percentage of awards granted | 33.33% |  |
Performance Shares |  |  |
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items] |  |  |
New stock option awards granted vest period | 3 years |  |
Unrecognized compensation cost for non-vested options | $ 7.8 |  |
Weighted-average period | 1 year 9 months 18 days |  |
Percentage of maximum increase in number of shares participant receives based on achievement of performance goals | 200.00% |  |
Potential lowest number of shares participant receives based on achievement of performance goals | 0.00% |  |
Vested (in shares) | shares | 32,130 | 43,198 | 43,621
Restricted Stock Units (RSUs) |  |  |
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items] |  |  |
New stock option awards granted vest period | 3 years |  |
Unrecognized compensation cost for non-vested options | $ 3.8 |  |
Weighted-average period | 1 year 6 months |  |
Total fair value of restricted shares vested | $ 3.0 | $ 0.5 | $ 3.2
Vested (in shares) | shares | 38,303 |  |
The 2010 Plan and the 2017 Plan |  |  |
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items] |  |  |
Shares reserved for issuance (in shares) | shares | 1,111,646 |  |
The 2020 Plan |  |  |
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items] |  |  |
Shares reserved for issuance (in shares) | shares | 975,475 |  |

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- Definition The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Publisher FASB -URI https://asc.fasb.org//1943274/2147480429/718-10-50-2 + Details
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