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Goodwill and Other Intangible Assets - Schedule of Acquisition Date Fair Values, Accumulated Amortization and Net Carrying Values for Other Intangibles Assets and Goodwill, By Company (Details) - USD ($) $ in Millions | 3 Months Ended |
--- | --- | ---
Mar. 31, 2023 | Dec. 31, 2022
Acquired Finite-Lived Intangible Assets [Line Items] |  |
Goodwill, acquisition date fair value | $ 168.8 | $ 176.5
Goodwill | 168.8 | 176.5
Total Equity Including Noncontrolling Interest |  |
Acquired Finite-Lived Intangible Assets [Line Items] |  |
Other intangible assets, accumulated amortization | 11.4 | 12.2
Total goodwill and other intangible assets | 387.6 | 404.6
Total goodwill and other intangible assets | 376.2 | 392.4
Other |  |
Acquired Finite-Lived Intangible Assets [Line Items] |  |
Other intangible assets, acquisition date fair value | 218.8 | 228.1
Other intangible assets, accumulated amortization | 11.4 | 12.2
Other intangible assets, net carrying value | 207.4 | 215.9
Ark |  |
Acquired Finite-Lived Intangible Assets [Line Items] |  |
Goodwill, acquisition date fair value | 116.8 | 116.8
Goodwill | 116.8 | 116.8
Indefinite-Lived Intangible Assets (Excluding Goodwill) | 175.7 | 175.7
Asset Management (Kudu) |  |
Acquired Finite-Lived Intangible Assets [Line Items] |  |
Goodwill, acquisition date fair value | 7.6 | 7.6
Goodwill | $ 7.6 | 7.6
Asset Management (Kudu) | Trade names |  |
Acquired Finite-Lived Intangible Assets [Line Items] |  |
Other intangible assets, weighted average useful life (in years) | 7 years |
Other intangible assets, acquisition date fair value | $ 2.2 | 2.2
Other intangible assets, accumulated amortization | 1.3 | 1.2
Other intangible assets, net carrying value | 0.9 | 1.0
Other Operations |  |
Acquired Finite-Lived Intangible Assets [Line Items] |  |
Goodwill, acquisition date fair value | 44.4 | 52.1
Goodwill | 44.4 | 52.1
Other intangible assets, acquisition date fair value | 40.9 | 50.2
Other intangible assets, accumulated amortization | 10.1 | 11.0
Other intangible assets, net carrying value | 30.8 | 39.2
Total goodwill and other intangible assets | $ 75.2 | 91.3
Other Operations | Trade names |  |
Acquired Finite-Lived Intangible Assets [Line Items] |  |
Other intangible assets, weighted average useful life (in years) | 13 years 3 months 18 days |
Other intangible assets, acquisition date fair value | $ 13.3 | 17.9
Other intangible assets, accumulated amortization | 2.6 | 3.0
Other intangible assets, net carrying value | $ 10.7 | 14.9
Other Operations | Customer relationships |  |
Acquired Finite-Lived Intangible Assets [Line Items] |  |
Other intangible assets, weighted average useful life (in years) | 11 years |
Other intangible assets, acquisition date fair value | $ 24.8 | 29.5
Other intangible assets, accumulated amortization | 7.0 | 7.5
Other intangible assets, net carrying value | $ 17.8 | 22.0
Other Operations | Other |  |
Acquired Finite-Lived Intangible Assets [Line Items] |  |
Other intangible assets, weighted average useful life (in years) | 12 years 1 month 6 days |
Other intangible assets, acquisition date fair value | $ 2.8 | 2.8
Other intangible assets, accumulated amortization | 0.5 | 0.5
Other intangible assets, net carrying value | $ 2.3 | $ 2.3

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