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Goodwill and Other Intangible Assets - Schedule of Goodwill and Other Intangible Assets Rollforward (Details) - USD ($) $ in Millions | 3 Months Ended
--- | ---
Mar. 31, 2023 | Mar. 31, 2022
Acquired Finite-Lived Intangible Assets [Line Items] |  |
Goodwill, beginning balance | $ 176.5 |
Goodwill, ending balance | 168.8 |
Goodwill |  |
Acquired Finite-Lived Intangible Assets [Line Items] |  |
Goodwill, beginning balance | 176.5 | $ 142.3
Dispositions | (6.7) | 0.0
Measurement period adjustments | (1.0) | 0.0
Amortization of other intangible assets | 0.0 | 0.0
Goodwill, ending balance | 168.8 | 142.3
Other |  |
Acquired Finite-Lived Intangible Assets [Line Items] |  |
Other intangible assets (excluding goodwill), beginning balance | 215.9 | 198.2
Dispositions | (6.9) | 0.0
Measurement period adjustments | 0.0 | 0.0
Amortization of other intangible assets | (1.6) | (1.0)
Other intangible assets (excluding goodwill), ending balance | 207.4 | 197.2
Total Goodwill and Other Intangible Assets |  |
Acquired Finite-Lived Intangible Assets [Line Items] |  |
Other intangible assets, gross (including goodwill), beginning balance | 392.4 | 340.5
Dispositions | (13.6) | 0.0
Measurement period adjustments | (1.0) | 0.0
Amortization of other intangible assets | (1.6) | (1.0)
Other intangible assets, gross (including goodwill), ending balance | $ 376.2 | $ 339.5

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