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Goodwill and Other Intangible Assets - Schedule of Goodwill and Other Intangible Assets Rollforward (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2021
Goodwill |  |  |
Goodwill, beginning balance | $ 176.5 | $ 142.3 |
Acquisitions of businesses | 0.0 | 59.5 |
Dispositions of businesses | (6.7) | 0.0 |
Attribution of acquisition date fair value estimates between goodwill and other intangible assets | 0.0 | (22.9) |
Measurement period adjustments | (1.0) | (2.4) |
Goodwill, ending balance | 168.8 | 176.5 | $ 142.3
Other Intangible Assets |  |  |
Other intangible assets (excluding goodwill), beginning balance | 215.9 | 198.2 |
Acquisition of businesses | 0.0 | 0.0 |
Dispositions of businesses | (6.9) | 0.0 |
Attribution of acquisition date fair value estimates between goodwill and other intangible assets | 0.0 | 22.9 |
Amortization | (7.2) | (5.2) | (4.6)
Other intangible assets (excluding goodwill), ending balance | 201.8 | 215.9 | 198.2
Total Goodwill and Other Intangible Assets |  |  |
Total Goodwill and Other Intangible Assets, beginning balance | 392.4 | 340.5 |
Acquisition of businesses | 0.0 | 59.5 |
Disposition of businesses | (13.6) | 0.0 |
Attribution of acquisition date fair value estimates between goodwill and other intangible assets | 0.0 | 0.0 |
Measurement period adjustments | (1.0) | (2.4) |
Amortization | (7.2) | (5.2) | (4.6)
Total Goodwill and Other Intangible Assets, ending balance | $ 370.6 | $ 392.4 | $ 340.5

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