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Derivatives - Gains (losses) included in the Statement of Earnings for changes in the fair value of derivatives (Details) - USD ($) $ in Millions | 3 Months Ended
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Mar. 31, 2023 | Mar. 31, 2022
Derivative Instruments and Hedging Activities Disclosures [Line Items] |  |
Derivatives not designated as hedges, gains (losses) included in net earnings | $ 7 | $ (5)
Earnings (losses) on derivatives | 2 | (4)
MBS with embedded derivatives |  |
Derivative Instruments and Hedging Activities Disclosures [Line Items] |  |
Derivatives not designated as hedges, gains (losses) included in net earnings | 1 | (5)
Total return swap |  |
Derivative Instruments and Hedging Activities Disclosures [Line Items] |  |
Derivatives not designated as hedges, gains (losses) included in net earnings | 6 | 0
Designated as hedging instrument | Interest rate swaps |  |
Derivative Instruments and Hedging Activities Disclosures [Line Items] |  |
Reclassification from accumulated other comprehensive income | $ (5) | $ 1

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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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- Definition Amount of realized and unrealized gain (loss) of derivative instruments not designated or qualifying as hedging instruments. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4CC -URI https://asc.fasb.org/extlink&oid=125515794&loc=SL109998890-113959 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4C -Subparagraph (e) -URI https://asc.fasb.org/extlink&oid=125515794&loc=SL5624171-113959 + Details
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- Definition Aggregate net gain (loss) on all derivative instruments recognized in earnings during the period, before tax effects. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4A -Subparagraph (b) -URI https://asc.fasb.org/extlink&oid=125515794&loc=SL5618551-113959 + Details
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- Definition Amount before tax of reclassification adjustments of other comprehensive income (loss). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 50 -Paragraph 5 -URI https://asc.fasb.org/extlink&oid=124431353&loc=SL124442411-227067 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 830 -SubTopic 30 -Section 45 -Paragraph 17 -URI https://asc.fasb.org/extlink&oid=118261656&loc=d3e32136-110900 Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 50 -Paragraph 4 -URI https://asc.fasb.org/extlink&oid=124431353&loc=SL124442407-227067 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 14A -URI https://asc.fasb.org/extlink&oid=126968391&loc=SL7669686-108580 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 830 -SubTopic 30 -Section 50 -Paragraph 1 -URI https://asc.fasb.org/extlink&oid=6450520&loc=d3e32583-110901 Reference 6: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 830 -SubTopic 30 -Section 45 -Paragraph 20 -Subparagraph (d) -URI https://asc.fasb.org/extlink&oid=118261656&loc=d3e32211-110900 + Details
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