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v3.23.1

Transactions With Related Parties (Details) - USD ($) $ in Millions | 3 Months Ended |  |
--- | --- | --- | ---
Mar. 31, 2023 | Mar. 31, 2022 | Dec. 31, 2022 | Dec. 31, 2021
Related Party Transaction [Line Items] |  |  |  |
Premiums ceded | $ 1,356 | $ 1,167 |  |
Reinsurance recoverable on unpaid and paid losses and loss adjustment expenses | 6,612 | 5,941 | $ 6,564 | $ 5,881
Reinsurance balances payable | 1,819 |  | 1,530 |
Net premiums written | 3,424 | 2,634 |  |
Net premiums earned | $ 2,883 | 2,121 |  |
Greysbridge Holdings Ltd |  |  |  |
Related Party Transaction [Line Items] |  |  |  |
Percentage ownership | 40.00% |  |  |
Operating affiliates | Somers Holdings Ltd |  |  |  |
Related Party Transaction [Line Items] |  |  |  |
Premiums ceded | $ 219 | 221 |  |
Reinsurance recoverable on unpaid and paid losses and loss adjustment expenses | 1,200 |  | 1,200 |
Reinsurance balances payable | 435 |  | 414 |
Equity Method Investee | Premia Holdings Ltd |  |  |  |
Related Party Transaction [Line Items] |  |  |  |
Net premiums written | 75 | 1 |  |
Net premiums earned | 75 | $ 1 |  |
Funds Held under Reinsurance Agreements, Asset | $ 199 |  | $ 119 |

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- Definition The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 323 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 3 -Subparagraph (a)(1) -Publisher FASB -URI https://asc.fasb.org//1943274/2147481687/323-10-50-3 + Details
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- Definition Amount of the reinsurer's funds held on its behalf by the ceding insurer, including funds held in trust, under reinsurance treaties or contracts with the assuming insurer as security for the payment of the obligations thereunder. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 944 -SubTopic 210 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(a)(10)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147479440/944-210-S99-1 + Details
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- Definition Amount, after premiums ceded to other entities and premiums assumed by the entity, of premiums earned. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 944 -SubTopic 235 -Name Accounting Standards Codification -Section S99 -Paragraph 2 -Subparagraph (SX 210.12-17(Column E)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480149/944-235-S99-2 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 944 -SubTopic 605 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (c)(3) -Publisher FASB -URI https://asc.fasb.org//1943274/2147479655/944-605-50-1 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-04(13)(c)) -SubTopic 220 -Topic 942 -Publisher FASB -URI https://asc.fasb.org//1943274/2147483589/942-220-S99-1 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-04(1)) -SubTopic 220 -Topic 944 -Publisher FASB -URI https://asc.fasb.org//1943274/2147483586/944-220-S99-1 + Details
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