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Share-Based Compensation - Performance Restricted Stock Units Narrative (Details) shares in Thousands, $ in Millions | 3 Months Ended | 12 Months Ended |
--- | --- | --- | ---
Mar. 31, 2021 | Dec. 31, 2022 USD ($) shares | Dec. 31, 2021 USD ($) entity shares | Dec. 31, 2020 USD ($) shares | Dec. 31, 2019 shares
PRSUs |  |  |  |  |
Share-based compensation |  |  |  |  |
Number of restricted stocks units granted (in shares) |  | 341 | 189 | 292 |
Net reduction in number of awards with performance against target (in shares) |  | 376 | 56 | 99 |
Increase in number of awards against target performance (in shares) |  |  |  | 1 |
Unvested restricted stock units outstanding (in shares) |  | 280 | 388 | 333 | 260
PRSUs | Executive and senior officers |  |  |  |  |
Share-based compensation |  |  |  |  |
Performance payout period | 1 year | 1 year |  |  |
Number of metrics | entity |  |  | 3 |  |
Average share price trading period |  |  | 20 days | 20 days |
Share price, last day in trading period |  |  | 20 days | 20 days |
Requisite service period |  | 5 years |  |  |
Recognized share-based compensation expense | $ |  | $ 1.2 | $ 1.4 | $ 1.2 |
Unrecognized compensation cost, net of estimated forfeitures, related to restricted stock unit awards | $ |  | $ 1.2 |  |  |
Weighted-average period over which unrecognized compensation cost is expected to be recognized |  | 1 year 3 months 18 days |  |  |
Income tax benefit recognized on share-based compensation | $ |  | $ 1.6 | $ 1.4 | $ 0.6 |
Vesting period |  | 4 years |  |  |
Restricted Stock Units |  |  |  |  |
Share-based compensation |  |  |  |  |
Number of restricted stocks units granted (in shares) |  | 687 | 528 | 782 |
Unvested restricted stock units outstanding (in shares) |  | 1,415 | 1,208 | 1,076 | 559
Recognized share-based compensation expense | $ |  | $ 3.7 | $ 3.5 | $ 4.4 |
Unrecognized compensation cost, net of estimated forfeitures, related to restricted stock unit awards | $ |  | $ 6.6 |  |  |
Weighted-average period over which unrecognized compensation cost is expected to be recognized |  | 2 years 7 months 6 days |  |  |
Vesting period |  | 4 years |  |  |
Restricted Stock Units | Executive and senior officers |  |  |  |  |
Share-based compensation |  |  |  |  |
Dividend yield |  |  | 0.00% |  |

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- Definition Represents the performance period of the entity, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References No definition available. + Details
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