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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 | 9 Months Ended |
--- | --- | ---
Sep. 30, 2022 | Dec. 31, 2021
Acquired Finite-Lived Intangible Assets [Line Items] |  |
Goodwill, acquisition date fair value | $ 175.5 | $ 142.3
Goodwill, net carrying value | 175.5 | 142.3
Total Equity Including Noncontrolling Interest |  |
Acquired Finite-Lived Intangible Assets [Line Items] |  |
Other intangible assets, acquisition date fair value | 403.6 | 347.5
Other intangible assets, accumulated amortization | 10.4 | 7.0
Total goodwill and other intangible assets | 393.2 | 340.5
Non-controlling interest |  |
Acquired Finite-Lived Intangible Assets [Line Items] |  |
Total goodwill and other intangible assets | 103.1 | 91.8
Total |  |
Acquired Finite-Lived Intangible Assets [Line Items] |  |
Total goodwill and other intangible assets | 290.1 | 248.7
Other |  |
Acquired Finite-Lived Intangible Assets [Line Items] |  |
Other intangible assets, acquisition date fair value | 228.1 | 205.2
Other intangible assets, accumulated amortization | 10.4 | 7.0
Other intangible assets, net carrying value | 217.7 | 198.2
Ark |  |
Acquired Finite-Lived Intangible Assets [Line Items] |  |
Goodwill, acquisition date fair value | 116.8 | 116.8
Goodwill, net carrying value | 116.8 | 116.8
Ark | Trade names |  |
Acquired Finite-Lived Intangible Assets [Line Items] |  |
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, net carrying value | $ 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 | 1.1 | 0.9
Other intangible assets, net carrying value | 1.1 | 1.3
Other Operations |  |
Acquired Finite-Lived Intangible Assets [Line Items] |  |
Goodwill, acquisition date fair value | 51.1 | 17.9
Goodwill, net carrying value | 51.1 | 17.9
Other intangible assets, acquisition date fair value | 50.2 | 27.3
Other intangible assets, accumulated amortization | 9.3 | 6.1
Other intangible assets, net carrying value | $ 40.9 | 21.2
Other Operations | Trade names |  |
Acquired Finite-Lived Intangible Assets [Line Items] |  |
Other intangible assets, weighted average useful life (in years) | 15 years 10 months 24 days |
Other intangible assets, acquisition date fair value | $ 17.9 | 8.2
Other intangible assets, accumulated amortization | 2.4 | 1.5
Other intangible assets, net carrying value | $ 15.5 | 6.7
Other Operations | Customer relationships |  |
Acquired Finite-Lived Intangible Assets [Line Items] |  |
Other intangible assets, weighted average useful life (in years) | 12 years 4 months 24 days |
Other intangible assets, acquisition date fair value | $ 29.5 | 18.8
Other intangible assets, accumulated amortization | 6.6 | 4.5
Other intangible assets, net carrying value | $ 22.9 | 14.3
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 | 0.3
Other intangible assets, accumulated amortization | 0.3 | 0.1
Other intangible assets, net carrying value | $ 2.5 | $ 0.2

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