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Summary of Significant Accounting Policies (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2021
Accounting Policies [Abstract] |  |  |
Unbilled Audit Premiums | $ 19 | $ 25 | $ 10
Weighted average shares held in grantor trust | 11,663,450 |  |
Indefinite-lived Intangible Assets [Line Items] |  |  |
Basic weighted average number of shares outstanding (in shares) | 271,000 | 276,852 | 277,430
Deposit contracts, liabilities | $ 31 | $ 33 |
Depreciation | 51 | 52 | $ 52
Interest payments | 114 | 138 | 141
Income taxes paid | 332 | 295 | $ 244
Other Assets |  |  |
Indefinite-lived Intangible Assets [Line Items] |  |  |
Intangible assets, net (excluding goodwill) | $ 119 | $ 102 |

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- Definition Carrying amount of liabilities as of the balance sheet date pertaining to amounts received by the insurer or reinsurer from the insured (including a ceding company) under insurance or reinsurance contracts for which insurance risk is not transferred. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 340 -SubTopic 30 -Name Accounting Standards Codification -Section 45 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org//1943274/2147483081/340-30-45-1 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 340 -SubTopic 30 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org//1943274/2147483054/340-30-50-1 + Details
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