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Significant Transactions (Tables) | 12 Months Ended
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Dec. 31, 2025
Significant Transactions [Abstract] |
Schedule of assets acquired and liabilities assumed | The following presents additional details of the net assets acquired as of the September 2, 2025 acquisition date:
Millions |  | As of September 2, 2025 |
Short-term investments, at fair value |  | $ | 78.1 |
Cash (restricted $0.4) |  | 1.1 |
Premiums, commissions and fees receivable |  | 34.6 |
Other assets |  | 11.3 |
Debt |  | (100.6) |
Premiums and commissions payable |  | (72.9) |
Other liabilities |  | (52.2) |
Net tangible assets acquired (liabilities assumed) |  | (100.6) |
Goodwill |  | 420.6 |
Other intangible assets |  | 198.2 |
Deferred tax liabilities related to investment basis differences |  | (24.0) |
Net assets acquired |  | $ | 494.2 |

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- Definition Tabular disclosure of asset acquired and liability assumed in business combination and recognized at acquisition date. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 805 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479907/805-20-50-2 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 805 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (c) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479907/805-20-50-1 + Details
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