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Goodwill and Other Intangible Assets - Summary of Goodwill and Intangible Assets (Details) - USD ($) $ in Millions | 12 Months Ended |
--- | --- | ---
Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019
Goodwill [Line Items] |  |  |
Goodwill, fair value | $ 675.7 | $ 525.5 |
Goodwill, impairment loss | 30.2 | 0.0 |
Goodwill | 645.5 | 525.5 |
Other intangible assets, fair value | 1,196.1 | 843.3 |
Other intangible assets, accumulated amortization | 93.8 | 54.7 |
Other intangible assets, net | 244.7 |  |
Goodwill and intangible asset impairment | 36.4 | 6.2 |
Ark |  |  |
Goodwill [Line Items] |  |  |
Goodwill, fair value | 116.8 | 0.0 |
Goodwill, impairment loss | 0.0 | 0.0 |
Goodwill | 116.8 | 0.0 |
NSM |  |  |
Goodwill [Line Items] |  |  |
Goodwill, fair value | 533.4 | 506.4 |
Goodwill, impairment loss | 30.2 | 0.0 |
Goodwill | 503.2 | 506.4 |
Other intangible assets, fair value | 315.2 | 288.9 |
Other intangible assets, accumulated amortization | 86.8 | 52.3 |
Impairments and Amounts Allocated to Held for Sale | 6.2 | 6.2 |
Other intangible assets, net | 222.2 | 230.4 |
Kudu |  |  |
Goodwill [Line Items] |  |  |
Goodwill, fair value | 7.6 | 7.6 |
Goodwill, impairment loss | 0.0 | 0.0 |
Goodwill | 7.6 | 7.6 |
Other |  |  |
Goodwill [Line Items] |  |  |
Goodwill, fair value | 17.9 | 11.5 |
Goodwill, impairment loss | 0.0 | 0.0 |
Goodwill | 17.9 | 11.5 |
Other intangible assets, fair value | 27.3 | 26.7 |
Other intangible assets, accumulated amortization | 6.1 | 1.8 |
Impairments and Amounts Allocated to Held for Sale | 0.0 |  |
Other intangible assets, net | 21.2 | 24.9 |
Trade names | Ark |  |  |
Goodwill [Line Items] |  |  |
Other intangible assets, fair value | 175.7 | 0.0 |
Other intangible assets, accumulated amortization | 0.0 | 0.0 |
Impairments and Amounts Allocated to Held for Sale | 0.0 | 0.0 |
Other intangible assets, net | $ 175.7 | 0.0 |
Trade names | NSM |  |  |
Goodwill [Line Items] |  |  |
Acquired other intangible assets, weighted average useful life (in years) | 18 years |  |
Other intangible assets, fair value | $ 68.6 | 65.4 |
Other intangible assets, accumulated amortization | 11.9 | 8.3 |
Impairments and Amounts Allocated to Held for Sale | 1.0 | 1.0 |
Other intangible assets, net | $ 55.7 | 56.1 |
Trade names | Kudu |  |  |
Goodwill [Line Items] |  |  |
Acquired other intangible assets, weighted average useful life (in years) | 7 years |  |
Other intangible assets, fair value | $ 2.2 | 2.2 |
Other intangible assets, accumulated amortization | 0.9 | 0.6 |
Impairments and Amounts Allocated to Held for Sale | 0.0 | 0.0 |
Other intangible assets, net | $ 1.3 | 1.6 |
Trade names | Other |  |  |
Goodwill [Line Items] |  |  |
Acquired other intangible assets, weighted average useful life (in years) | 17 years 6 months |  |
Other intangible assets, fair value | $ 8.2 | 3.6 |
Other intangible assets, accumulated amortization | 1.5 | 0.3 |
Impairments and Amounts Allocated to Held for Sale | 0.0 | 0.0 |
Other intangible assets, net | $ 6.7 | 3.3 |
Customer relationships | NSM |  |  |
Goodwill [Line Items] |  |  |
Acquired other intangible assets, weighted average useful life (in years) | 9 years |  |
Other intangible assets, fair value | $ 159.9 | 136.2 |
Other intangible assets, accumulated amortization | 57.0 | 36.7 |
Impairments and Amounts Allocated to Held for Sale | 3.5 | 3.5 |
Other intangible assets, net | $ 99.4 | 96.0 |
Customer relationships | Other |  |  |
Goodwill [Line Items] |  |  |
Acquired other intangible assets, weighted average useful life (in years) | 13 years |  |
Other intangible assets, fair value | $ 18.8 | 14.2 |
Other intangible assets, accumulated amortization | 4.5 | 1.4 |
Impairments and Amounts Allocated to Held for Sale | 0.0 | 0.0 |
Other intangible assets, net | $ 14.3 | 12.8 |
Information technology platform | NSM |  |  |
Goodwill [Line Items] |  |  |
Acquired other intangible assets, weighted average useful life (in years) | 0 years |  |
Other intangible assets, fair value | $ 3.1 | 3.1 |
Other intangible assets, accumulated amortization | 1.4 | 1.4 |
Impairments and Amounts Allocated to Held for Sale | 1.7 | 1.7 |
Other intangible assets, net | $ 0.0 | 0.0 |
Renewal rights | NSM |  |  |
Goodwill [Line Items] |  |  |
Acquired other intangible assets, weighted average useful life (in years) | 12 years |  |
Other intangible assets, fair value | $ 82.5 | 82.5 |
Other intangible assets, accumulated amortization | 15.8 | 4.9 |
Impairments and Amounts Allocated to Held for Sale | 0.0 | 0.0 |
Other intangible assets, net | 66.7 | 77.6 |
Insurance licenses (2) | Other |  |  |
Goodwill [Line Items] |  |  |
Other intangible assets, fair value | 0.0 | 8.6 |
Other intangible assets, accumulated amortization | 0.0 | 0.0 |
Impairments and Amounts Allocated to Held for Sale | 0.0 | 0.0 |
Other intangible assets, net | 0.0 | 8.6 |
Insurance licenses (2) | Other | Disposal Group, Held-for-sale, Not Discontinued Operations |  |  |
Goodwill [Line Items] |  |  |
Other intangible assets, net | $ 8.6 |  |
Other | NSM |  |  |
Goodwill [Line Items] |  |  |
Acquired other intangible assets, weighted average useful life (in years) | 3 years 3 months 18 days |  |
Other intangible assets, fair value | $ 1.1 | 1.7 |
Other intangible assets, accumulated amortization | 0.7 | 1.0 |
Impairments and Amounts Allocated to Held for Sale | 0.0 | 0.0 |
Other intangible assets, net | $ 0.4 | 0.7 |
Other | Other |  |  |
Goodwill [Line Items] |  |  |
Acquired other intangible assets, weighted average useful life (in years) | 5 years 3 months 18 days |  |
Other intangible assets, fair value | $ 0.3 | 0.3 |
Other intangible assets, accumulated amortization | 0.1 | 0.1 |
Impairments and Amounts Allocated to Held for Sale | 0.0 | 0.0 |
Other intangible assets, net | 0.2 | 0.2 |
Total other intangible assets |  |  |
Goodwill [Line Items] |  |  |
Other intangible assets, fair value | 520.4 | 317.8 |
Other intangible assets, accumulated amortization | 93.8 | 54.7 |
Impairments and Amounts Allocated to Held for Sale | 6.2 | 6.2 |
Other intangible assets, net | 420.4 | 256.9 |
Total Equity |  |  |
Goodwill [Line Items] |  |  |
Goodwill and other intangible assets | 1,065.9 | 782.4 |
Non-controlling Interests |  |  |
Goodwill [Line Items] |  |  |
Goodwill and other intangible assets | (117.6) | (28.1) |
Total |  |  |
Goodwill [Line Items] |  |  |
Goodwill and other intangible assets | 948.3 | 754.3 |
Goodwill |  |  |
Goodwill [Line Items] |  |  |
Goodwill, impairment loss | 0.0 | 0.0 |
Goodwill | 645.5 | 525.5 | $ 394.7
Goodwill, foreign currency translation gain | (1.5) | 13.4 |
Goodwill | NSM |  |  |
Goodwill [Line Items] |  |  |
Goodwill, foreign currency translation gain | (1.5) | 13.4 |
Total other intangible assets |  |  |
Goodwill [Line Items] |  |  |
Goodwill, impairment loss | 0.0 | 6.2 |
Total other intangible assets | NSM |  |  |
Goodwill [Line Items] |  |  |
Goodwill, foreign currency translation gain | $ (0.3) | $ 1.6 |

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