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Derivative Instruments (Narrative) (Detail) $ in Millions | Mar. 31, 2023 USD ($) | Dec. 31, 2022 USD ($)
--- | --- | ---
Derivative [Line Items] |  |
Cash collateral posted to derivative counterparties | $ 0 | $ 0
Securities posted as collateral to derivative counterparties | $ 85 | $ 73
Number of credit support annexes | 1 | 1
Fair value of credit support annexes | $ (1) | $ (1)

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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 -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 55 -Paragraph 13 -URI https://asc.fasb.org/extlink&oid=99393222&loc=SL20226016-175313 Reference 2: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 55 -Paragraph 20 -URI https://asc.fasb.org/extlink&oid=99393222&loc=SL20226038-175313 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 8 -Subparagraph (b) -URI https://asc.fasb.org/extlink&oid=125515794&loc=d3e41678-113959 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 50 -Paragraph 3 -Subparagraph (d)(2) -URI https://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312 + Details
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