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Employee Share-Based Incentive Compensation Plans - Narrative (Details) $ in Millions | 12 Months Ended | 36 Months Ended |
--- | --- | --- | ---
Dec. 31, 2023 USD ($) shares | Dec. 31, 2022 USD ($) shares | Dec. 31, 2021 USD ($) shares | Dec. 31, 2021 USD ($) shares | Dec. 31, 2020 USD ($)
Share-based compensation arrangement by share-based payment award |  |  |  |  |
Grants in period (in shares) | 10,895 | 13,225 | 13,475 |  |
Performance Shares |  |  |  |  |
Share-based compensation arrangement by share-based payment award |  |  |  |  |
Vesting period | 3 years |  |  |  |
Performance cycle period | 3 years |  |  |  |
New grants (in shares) |  |  |  | 750 |
Additional compensation cost that would be recognized if all outstanding performance shares vested | $ | $ 27.9 |  |  |  |
Performance Shares | 2023 – 2025 |  |  |  |  |
Share-based compensation arrangement by share-based payment award |  |  |  |  |
Targeted performance goal (as a percent) | 11.00% |  |  |  |
Payout maximum growth target percentage | 200.00% |  |  |  |
Performance Shares | 2022 – 2024 |  |  |  |  |
Share-based compensation arrangement by share-based payment award |  |  |  |  |
Targeted performance goal (as a percent) | 9.00% |  |  |  |
Payout maximum growth target percentage | 200.00% |  |  |  |
Performance Shares | 2023 – 2025 |  |  |  |  |
Share-based compensation arrangement by share-based payment award |  |  |  |  |
Targeted performance goal (as a percent) | 8.00% |  |  |  |
Payout maximum growth target percentage | 200.00% |  |  |  |
Performance Shares | Minimum |  |  |  |  |
Share-based compensation arrangement by share-based payment award |  |  |  |  |
Share-based compensation arrangement by share-based payment award, multiplier | 0 |  |  |  |
Performance Shares | Minimum | 2023 – 2025 |  |  |  |  |
Share-based compensation arrangement by share-based payment award |  |  |  |  |
Payout range for growth target percentage | 6.00% |  |  |  |
Performance Shares | Minimum | 2022 – 2024 |  |  |  |  |
Share-based compensation arrangement by share-based payment award |  |  |  |  |
Payout range for growth target percentage | 4.00% |  |  |  |
Performance Shares | Minimum | 2023 – 2025 |  |  |  |  |
Share-based compensation arrangement by share-based payment award |  |  |  |  |
Payout range for growth target percentage | 3.00% |  |  |  |
Performance Shares | Maximum |  |  |  |  |
Share-based compensation arrangement by share-based payment award |  |  |  |  |
Share-based compensation arrangement by share-based payment award, multiplier | 2 |  |  |  |
Performance Shares | Maximum | 2023 – 2025 |  |  |  |  |
Share-based compensation arrangement by share-based payment award |  |  |  |  |
Payout range for growth target percentage | 16.00% |  |  |  |
Performance Shares | Maximum | 2022 – 2024 |  |  |  |  |
Share-based compensation arrangement by share-based payment award |  |  |  |  |
Payout range for growth target percentage | 14.00% |  |  |  |
Performance Shares | Maximum | 2023 – 2025 |  |  |  |  |
Share-based compensation arrangement by share-based payment award |  |  |  |  |
Payout range for growth target percentage | 13.00% |  |  |  |
Restricted Stock |  |  |  |  |
Share-based compensation arrangement by share-based payment award |  |  |  |  |
Vesting period | 34 months |  |  |  |
Additional compensation cost that would be recognized if all outstanding performance shares vested | $ | $ 16.2 | $ 15.5 | $ 15.9 | $ 15.9 | $ 15.2
Issued (in shares) | 10,895 | 13,225 | 13,475 |  |

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