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Derivative Instruments (Narrative) (Detail) $ in Millions | Sep. 30, 2023 USD ($) CreditSupportAnnex | Dec. 31, 2022 USD ($) CreditSupportAnnex
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Derivative [Line Items] |  |
Cash collateral posted to derivative counterparties | $ 0 | $ 0
Securities posted as collateral to derivative counterparties | $ 40 | $ 73
Number of credit support annexes | CreditSupportAnnex | 1 | 1
Fair value of credit support annexes | $ (1) | $ (1)

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- Definition Number of credit support annexes which define the terms or rules under which collateral is posted or transferred between swap counterparties to mitigate the credit risk arising from "in the money" derivative positions. + References No definition available. + Details
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- Definition Amount of right to receive cash collateral under master netting arrangements that have not been offset against derivative liabilities. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Section 55 -Paragraph 13 -SubTopic 20 -Topic 210 -Publisher FASB -URI https://asc.fasb.org//1943274/2147483444/210-20-55-13 Reference 2: http://www.xbrl.org/2003/role/exampleRef -Topic 210 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 20 -Publisher FASB -URI https://asc.fasb.org//1943274/2147483444/210-20-55-20 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 210 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 3 -Subparagraph (d)(2) -Publisher FASB -URI https://asc.fasb.org//1943274/2147483466/210-20-50-3 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 8 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480434/815-10-50-8 + Details
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