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Significant Transactions (Tables) | 12 Months Ended
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Dec. 31, 2023
Significant Transactions [Abstract] |
Schedule of assets acquired and liabilities assumed | The following presents additional details of the assets acquired and liabilities assumed as of the January 1, 2021 acquisition date:
Millions |  | As of January 1, 2021 |
Investments |  | $ | 594.3 |
Cash |  | 52.0 | (1)
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 |
(1) Cash excludes the White Mountains cash contribution of $605.4 as part of the Ark Transaction.

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- Definition Tabular disclosure of the amounts recognized as of the acquisition date for each major class of assets acquired and liabilities assumed. May include but not limited to the following: (a) acquired receivables; (b) contingencies recognized at the acquisition date; and (c) the fair value of noncontrolling interests in the acquiree. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 805 -SubTopic 20 -Name Accounting Standards Codification -Paragraph 1 -Section 50 -Publisher FASB -URI https://asc.fasb.org//1943274/2147479907/805-20-50-1 + Details
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