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Future Policy Benefit Reserves - Narrative (Details) - USD ($) | 3 Months Ended
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Mar. 31, 2023 | Mar. 31, 2022
Insurance [Abstract] |  |
Insurance claims and policyholders benefits, including policyholders' dividends, remeasurement impact | $ 1,000,000 | $ 5,000,000
Liability for future policy benefit, gross premium income | 115,000,000 | 120,000,000
Liability for future policy benefit, expected future gross premium, discounted, before reinsurance | $ 4,046,000,000 | $ 4,567,000,000
Liability for future policy benefit, weighted-average duration | 12 years | 12 years
Liability for future policy benefit, adverse development, expense | $ 13,000,000 | $ 0
Liability future policy benefit, losses recognized in prior period | $ 11,000,000 | $ 1,000,000

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- Definition Insurance Claims And Policyholders Benefits, Including Policyholders' Dividends, Remeasurement Impact + References No definition available. + Details
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- Definition Liability For Future Policy Benefit, Losses Recognized In Prior Period Reversed Due To Favorable Development + References No definition available. + Details
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- Definition Amount of expense for adverse development on liability of future policy benefit from net premium exceeding gross premium. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 40 -Section 65 -Paragraph 2 -Subparagraph (g)(2)(iii) -URI https://asc.fasb.org/extlink&oid=124501264&loc=SL117420844-207641 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 40 -Section 50 -Paragraph 6 -Subparagraph (d) -URI https://asc.fasb.org/extlink&oid=124506351&loc=d3e14931-158439 + Details
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- Definition Amount, before effect of reinsurance, of discounted balance for expected future gross premium component of liability for future policy benefit. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 40 -Section 50 -Paragraph 6 -Subparagraph (b)(1) -URI https://asc.fasb.org/extlink&oid=124506351&loc=d3e14931-158439 + Details
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- Definition Amount of gross premium income recognized for liability for future policy benefit. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 40 -Section 50 -Paragraph 6 -Subparagraph (b)(3) -URI https://asc.fasb.org/extlink&oid=124506351&loc=d3e14931-158439 Reference 2: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 40 -Section 55 -Paragraph 29E -URI https://asc.fasb.org/extlink&oid=126561865&loc=SL117819541-158441 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 40 -Section 50 -Paragraph 6 -Subparagraph (c) -URI https://asc.fasb.org/extlink&oid=124506351&loc=d3e14931-158439 + Details
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- Definition Weighted-average duration of liability for future policy benefit, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 40 -Section 50 -Paragraph 6 -Subparagraph (b)(5) -URI https://asc.fasb.org/extlink&oid=124506351&loc=d3e14931-158439 + Details
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