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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 | 6 Months Ended |
--- | --- | ---
Jun. 30, 2022 | Dec. 31, 2021
Acquired Finite-Lived Intangible Assets [Line Items] |  |
Goodwill, acquisition date fair value | $ 201.8 | $ 142.3
Goodwill, net carrying value | 201.8 | 142.3
Total Equity Including Noncontrolling Interest |  |
Acquired Finite-Lived Intangible Assets [Line Items] |  |
Other intangible assets, acquisition date fair value | 407.0 | 347.5
Other intangible assets, accumulated amortization | 9.0 | 7.0
Total goodwill and other intangible assets | 398.0 | 340.5
Non-controlling interest |  |
Acquired Finite-Lived Intangible Assets [Line Items] |  |
Total goodwill and other intangible assets | 103.4 | 91.8
Total |  |
Acquired Finite-Lived Intangible Assets [Line Items] |  |
Total goodwill and other intangible assets | 294.6 | 248.7
Other |  |
Acquired Finite-Lived Intangible Assets [Line Items] |  |
Other intangible assets, acquisition date fair value | 205.2 | 205.2
Other intangible assets, accumulated amortization | 9.0 | 7.0
Other intangible assets, net carrying value | 196.2 | 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] |  |
Other intangible assets, acquisition date fair value | 175.7 | 175.7
Other intangible assets, accumulated amortization | 0.0 | 0.0
Other intangible assets, net carrying value | 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 (1) |  |
Acquired Finite-Lived Intangible Assets [Line Items] |  |
Goodwill, acquisition date fair value | 77.4 | 17.9
Goodwill, net carrying value | 77.4 | 17.9
Other intangible assets, acquisition date fair value | 27.3 | 27.3
Other intangible assets, accumulated amortization | 7.9 | 6.1
Other intangible assets, net carrying value | $ 19.4 | 21.2
Other Operations (1) | Trade names |  |
Acquired Finite-Lived Intangible Assets [Line Items] |  |
Other intangible assets, weighted average useful life (in years) | 17 years 6 months |
Other intangible assets, acquisition date fair value | $ 8.2 | 8.2
Other intangible assets, accumulated amortization | 2.0 | 1.5
Other intangible assets, net carrying value | $ 6.2 | 6.7
Other Operations (1) | Customer relationships |  |
Acquired Finite-Lived Intangible Assets [Line Items] |  |
Other intangible assets, weighted average useful life (in years) | 13 years |
Other intangible assets, acquisition date fair value | $ 18.8 | 18.8
Other intangible assets, accumulated amortization | 5.7 | 4.5
Other intangible assets, net carrying value | $ 13.1 | 14.3
Other Operations (1) | Other |  |
Acquired Finite-Lived Intangible Assets [Line Items] |  |
Other intangible assets, weighted average useful life (in years) | 5 years 3 months 18 days |
Other intangible assets, acquisition date fair value | $ 0.3 | 0.3
Other intangible assets, accumulated amortization | 0.2 | 0.1
Other intangible assets, net carrying value | $ 0.1 | $ 0.2

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