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v3.22.1

Significant Transactions - Schedule of Assets Acquired and Liabilities Assumed, Ark (Details) - USD ($) $ in Millions | Oct. 01, 2020 | Mar. 31, 2022 | Dec. 31, 2021 | Jan. 01, 2021
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Other Significant Transactions [Line Items] |  |  |  |
Goodwill |  | $ 641.4 | $ 645.5 |
Ark |  |  |  |
Other Significant Transactions [Line Items] |  |  |  |
Investments |  |  |  | $ 594.3
Cash |  |  |  | 52.0
Reinsurance recoverables |  |  |  | 433.4
Insurance premiums receivable |  |  |  | 236.7
Ceded unearned premiums |  |  |  | 170.2
Value of in-force business acquired |  |  |  | 71.7
Other assets |  |  |  | 88.9
Loss and loss adjustment expense reserves |  |  |  | (696.0)
Unearned insurance premiums |  |  |  | (326.1)
Debt |  |  |  | (46.4)
Ceded reinsurance payable |  |  |  | (528.3)
Other liabilities |  |  |  | (25.9)
Net tangible assets acquired |  |  |  | 24.5
Goodwill |  |  |  | 116.8
Other intangible assets - syndicate underwriting capacity |  |  |  | 175.7
Deferred tax liability on other intangible assets |  |  |  | (33.4)
Net assets acquired |  |  |  | $ 283.6
Merger agreement, equity capital contributed | $ 605.4 |  |  |

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