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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, 2024 | Mar. 31, 2023
Goodwill |  |
Goodwill, beginning balance | $ 168.8 | $ 176.5
Acquisition of businesses | 270.4 | 0.0
Dispositions | 0.0 | (6.7)
Measurement period adjustments | 0.0 | (1.0)
Goodwill, ending balance | 439.2 | 168.8
Other Intangible Assets |  |
Other intangible assets (excluding goodwill), beginning balance | 201.8 | 215.9
Acquisition of businesses | 101.0 | 0.0
Acquisition of intangible assets | 0.3 | 0.0
Dispositions | 0.0 | (6.9)
Amortization | (5.7) | (1.6)
Other intangible assets (excluding goodwill), ending balance | 297.4 | 207.4
Total Goodwill and Other Intangible Assets |  |
Total Goodwill and Other Intangible Assets, beginning balance | 370.6 | 392.4
Acquisition of businesses | 371.4 | 0.0
Acquisition of intangible assets | 0.3 | 0.0
Dispositions | 0.0 | (13.6)
Measurement period adjustments | 0.0 | (1.0)
Amortization | (5.7) | (1.6)
Total Goodwill and Other Intangible Assets, ending balance | $ 736.6 | $ 376.2

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