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Benefit Plans - Allocation of Plan Assets (Details) - USD ($) $ in Millions | Dec. 31, 2022 | Dec. 31, 2021
--- | --- | ---
Defined Benefit Plan Disclosure [Line Items] |  |
Weighted average asset allocations | 100.00% | 100.00%
Fair value of plan assets | $ 29.4 | $ 249.2
Pension plan assets in the fair value hierarchy |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 29.4 | 49.5
Level 1 |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 0.7 | 1.6
Level 2 |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 28.7 | 47.9
Level 3 |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 0.0 | 0.0
Pension plan assets measured at NAV |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 0.0 | 199.7
Cash | Pension plan assets in the fair value hierarchy |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 0.7 | 1.6
Cash | Level 1 |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 0.7 | 1.6
Cash | Level 2 |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 0.0 | 0.0
Cash | Level 3 |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | $ 0.0 | $ 0.0
Equity securities |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Weighted average asset allocations | 28.00% | 12.00%
Equity securities | United States |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Target allocation | 27.00% |
Equity securities | Pension plan assets in the fair value hierarchy |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | $ 8.2 | $ 21.2
Equity securities | Level 1 |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 0.0 | 0.0
Equity securities | Level 2 |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 8.2 | 21.2
Equity securities | Level 3 |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | $ 0.0 | $ 0.0
Debt securities |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Weighted average asset allocations | 68.00% | 86.00%
Debt securities | United States |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Target allocation | 68.00% |
Other |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Weighted average asset allocations | 4.00% | 2.00%
Other | United States |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Target allocation | 5.00% |
Mutual funds | Pension plan assets in the fair value hierarchy |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | $ 20.4 | $ 22.1
Mutual funds | Level 1 |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 0.0 | 0.0
Mutual funds | Level 2 |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 20.4 | 22.1
Mutual funds | Level 3 |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 0.0 | 0.0
Other mutual funds | Pension plan assets in the fair value hierarchy |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 0.1 | 4.6
Other mutual funds | Level 1 |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 0.0 | 0.0
Other mutual funds | Level 2 |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 0.1 | 4.6
Other mutual funds | Level 3 |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | $ 0.0 | $ 0.0
Minimum | Equity securities | United States |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Weighted average asset allocations | 25.00% |
Minimum | Debt securities | United States |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Weighted average asset allocations | 63.00% |
Minimum | Other | United States |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Weighted average asset allocations | 2.00% |
Maximum | Equity securities | United States |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Weighted average asset allocations | 30.00% |
Maximum | Debt securities | United States |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Weighted average asset allocations | 68.00% |
Maximum | Other | United States |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Weighted average asset allocations | 7.00% |

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