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Goodwill and Other Intangible Assets - Schedule of Goodwill and Other Intangible Assets Rollforward (Details) - USD ($) $ in Millions | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2023 | Jun. 30, 2022 | Jun. 30, 2023 | Jun. 30, 2022
Acquired Finite-Lived Intangible Assets [Line Items] |  |  |  |
Goodwill, beginning balance |  |  | $ 176.5 |
Goodwill, ending balance | $ 168.8 |  | 168.8 |
Goodwill |  |  |  |
Acquired Finite-Lived Intangible Assets [Line Items] |  |  |  |
Goodwill, beginning balance | 168.8 | $ 142.3 | 176.5 | $ 142.3
Acquisition of businesses | 0.0 | 59.5 | 0.0 | 59.5
Dispositions |  |  | (6.7) | 0.0
Measurement period adjustments |  |  | (1.0) | 0.0
Amortization of other intangible assets | 0.0 | 0.0 | 0.0 | 0.0
Goodwill, ending balance | 168.8 | 201.8 | 168.8 | 201.8
Other |  |  |  |
Acquired Finite-Lived Intangible Assets [Line Items] |  |  |  |
Other intangible assets (excluding goodwill), beginning balance | 207.4 | 197.2 | 215.9 | 198.2
Acquisition of businesses | 0.0 | 0.0 | 0.0 | 0.0
Dispositions |  |  | (6.9) | 0.0
Measurement period adjustments |  |  | 0.0 | 0.0
Amortization of other intangible assets | (2.6) | (1.0) | (4.2) | (2.0)
Other intangible assets (excluding goodwill), ending balance | 204.8 | 196.2 | 204.8 | 196.2
Total Goodwill and Other Intangible Assets |  |  |  |
Acquired Finite-Lived Intangible Assets [Line Items] |  |  |  |
Other intangible assets, gross (including goodwill), beginning balance | 376.2 | 339.5 | 392.4 | 340.5
Acquisition of businesses | 0.0 | 59.5 | 0.0 | 59.5
Dispositions |  |  | (13.6) | 0.0
Measurement period adjustments |  |  | (1.0) | 0.0
Amortization of other intangible assets | (2.6) | (1.0) | (4.2) | (2.0)
Other intangible assets, gross (including goodwill), ending balance | $ 373.6 | $ 398.0 | $ 373.6 | $ 398.0

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