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Derivatives and Hedge Accounting Activities (Schedule of Amounts Recorded on Balance Sheet Related to Cumulative Basis Adjustments for Fair Value Hedges) (Parenthetical) (Detail) - Designated as Hedging Instrument - Fair Value Hedging - Long-term Debt - USD ($) $ in Millions | Dec. 31, 2020 | Dec. 31, 2019
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Derivative Instruments And Hedging Activities Disclosures [Line Items] |  |
Discontinued hedging liability | $ (1,153) | $ (397)
Hedging adjustments on discontinued hedging relationships | $ (3) | $ 3

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- Definition Hedged liability discontinued fair value hedge. + References No definition available. + Details
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- Definition Amount as of the balance sheet date of the unamortized adjustment to the carrying value of an interest-bearing hedged item made under an effective fair value hedge that is amortized upon discontinuation of the fair value hedge. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 25 -Section 35 -Paragraph 9 -URI http://asc.fasb.org/extlink&oid=121561968&loc=d3e75592-113984 + Details
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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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