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Employee Benefits - Plan Assets and Investment Policy (Details) - USD ($) $ in Millions | Dec. 31, 2024 | Dec. 31, 2023 | Dec. 31, 2022
--- | --- | --- | ---
Return Seeking Assets | Minimum |  |  |
Employee Benefits |  |  |
Weighted-average asset allocations (as a percent) | 50.00% |  |
Return Seeking Assets | Maximum |  |  |
Employee Benefits |  |  |
Weighted-average asset allocations (as a percent) | 70.00% |  |
Liability Hedging Assets | Minimum |  |  |
Employee Benefits |  |  |
Weighted-average asset allocations (as a percent) | 30.00% |  |
Liability Hedging Assets | Maximum |  |  |
Employee Benefits |  |  |
Weighted-average asset allocations (as a percent) | 50.00% |  |
DB Plan |  |  |
Employee Benefits |  |  |
Total investments at fair value | $ 65.6 | $ 63.8 | $ 56.7
DB Plan | Fair Value, Inputs, Level 1, Level 2, and Level 3 [Member] |  |  |
Employee Benefits |  |  |
Fair value of plan assets | 2.0 |  |
DB Plan | Level 1 |  |  |
Employee Benefits |  |  |
Total investments at fair value | 2.0 | 51.7 |
DB Plan | Level 2 |  |  |
Employee Benefits |  |  |
Total investments at fair value |  | 12.1 |
DB Plan | Fair Value Measured at Net Asset Value Per Share [Member] |  |  |
Employee Benefits |  |  |
Fair value of plan assets | 63.6 |  |
DB Plan | Common stock. |  |  |
Employee Benefits |  |  |
Fair value of plan assets |  | 37.8 |
DB Plan | Common stock. | Level 1 |  |  |
Employee Benefits |  |  |
Fair value of plan assets |  | 37.8 |
DB Plan | U.S. government, state, and agency |  |  |
Employee Benefits |  |  |
Fair value of plan assets |  | 8.3 |
DB Plan | U.S. government, state, and agency | Level 2 |  |  |
Employee Benefits |  |  |
Fair value of plan assets |  | 8.3 |
DB Plan | Corporate debt securities |  |  |
Employee Benefits |  |  |
Fair value of plan assets |  | 3.8 |
DB Plan | Corporate debt securities | Level 2 |  |  |
Employee Benefits |  |  |
Fair value of plan assets |  | 3.8 |
DB Plan | Mutual funds |  |  |
Employee Benefits |  |  |
Fair value of plan assets | 1.9 | 13.4 |
DB Plan | Mutual funds | Level 1 |  |  |
Employee Benefits |  |  |
Fair value of plan assets | 1.9 | 13.4 |
DB Plan | Interest bearing cash |  |  |
Employee Benefits |  |  |
Fair value of plan assets | 0.1 | 0.5 |
DB Plan | Interest bearing cash | Level 1 |  |  |
Employee Benefits |  |  |
Fair value of plan assets | $ 0.1 | $ 0.5 |

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