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Summary of Significant Accounting Policies (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2022 | Dec. 31, 2021 | Dec. 31, 2020
Accounting Policies [Abstract] |  |  |
Unbilled Audit Premiums | $ 25 | $ 10 | $ (27)
Weighted average shares held in grantor trust | 11,416,856 |  |
Indefinite-lived Intangible Assets [Line Items] |  |  |
Basic weighted average number of shares outstanding (in shares) | 276,852 | 277,430 | 280,386
Deposit contracts, liabilities | $ 33 | $ 35 |
Depreciation | 52 | 52 | $ 53
Interest payments | 138 | 141 | 155
Income taxes paid | 295 | 244 | $ 103
Other Assets |  |  |
Indefinite-lived Intangible Assets [Line Items] |  |  |
Intangible assets, net (excluding goodwill) | $ 102 | $ 85 |

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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 -Publisher FASB -Name Accounting Standards Codification -Topic 340 -SubTopic 30 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=99383045&loc=d3e9351-108337 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 340 -SubTopic 30 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=99397363&loc=d3e9420-108338 + Details
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