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Contracts Accounted for as Insurance - Deferred Acquisition Costs (Details) - USD ($) $ in Millions | 12 Months Ended
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Dec. 31, 2024 | Dec. 31, 2023 | Dec. 31, 2022
Movement Analysis of Deferred Policy Acquisition Costs [Roll Forward] |  |  |
Beginning of period | $ 161 | $ 147 | $ 131
Costs deferred during the period | 35 | 27 | 30
Costs amortized during the period | (20) | (13) | (14)
End of period | $ 176 | $ 161 | $ 147

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- Definition Deferred Policy Acquisition Cost, Amortization Expense, Including Accretion Of Discount On Commissions + References No definition available. + Details
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- Definition Amount of deferred policy acquisition cost capitalized on contract remaining in force. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 944 -SubTopic 40 -Name Accounting Standards Codification -Section 65 -Paragraph 2 -Subparagraph (g)(1) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480016/944-40-65-2 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 944 -SubTopic 30 -Name Accounting Standards Codification -Section 50 -Paragraph 2B -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479432/944-30-50-2B Reference 3: http://www.xbrl.org/2003/role/exampleRef -Topic 944 -SubTopic 30 -Name Accounting Standards Codification -Section 55 -Paragraph 2 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479401/944-30-55-2 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Topic 944 -SubTopic 210 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(a)(7)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147478777/944-210-S99-1 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Name Accounting Standards Codification -Section 45 -Paragraph 1 -SubTopic 825 -Topic 944 -Publisher FASB -URI https://asc.fasb.org/1943274/2147478219/944-825-45-1 Reference 6: http://www.xbrl.org/2003/role/disclosureRef -Topic 944 -SubTopic 30 -Name Accounting Standards Codification -Section 50 -Paragraph 2B -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479432/944-30-50-2B + Details
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