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Derivative Financial Instruments - Information about Fair Values of Derivative Instruments in Consolidated Statement of Income (Detail) - USD ($) $ in Millions | 12 Months Ended
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Dec. 31, 2024 | Dec. 31, 2023 | Dec. 31, 2022
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Derivatives not designated as hedging instruments, derivatives | $ 36 | $ 46 | $ 42
Interest rate swap agreements | Designated as Hedging Instrument | Fair Value Hedges |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Derivatives in fair value hedging relationships, derivative | (111) | 22 | (109)
Derivatives in fair value hedging relationships, hedged item | $ 111 | $ (21) | $ 109
Interest rate swap agreements | Fixed Rate Long-Term Borrowings | Designated as Hedging Instrument | Fair Value Hedges |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Derivative, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration] | Other costs of operations | Other costs of operations | Other costs of operations
Derivatives in fair value hedging relationships, derivative | $ (111) | $ 22 | $ (109)
Derivatives in fair value hedging relationships, hedged item | 111 | (21) | 109
Interest rate swap agreements | Fixed Rate Available For Sale Securities | Designated as Hedging Instrument | Fair Value Hedges |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Derivatives in fair value hedging relationships, derivative | 0 |  |
Derivatives in fair value hedging relationships, hedged item | 0 |  |
Interest Rate Contracts |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Derivatives not designated as hedging instruments, derivatives | 15 | 31 | 28
Foreign exchange and other option and futures contracts |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Derivatives not designated as hedging instruments, derivatives | $ 21 | $ 15 | $ 14

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- Definition Amount of increase (decrease) in the fair value of derivatives recognized in the income statement. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 815 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 4A -Subparagraph (b)(1) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480434/815-10-50-4A + Details
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- Definition Indicates line item in statement of income or comprehensive income that includes gain (loss) from derivative. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 815 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 4A -Subparagraph (b)(1) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480434/815-10-50-4A + 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 Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 815 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 4E -Publisher FASB -URI https://asc.fasb.org/1943274/2147480434/815-10-50-4E + Details
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- Definition Aggregate net gain and losses (whether realized or unrealized) on all derivative instruments held for trading purposes whether or not settled physically. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 45 -Paragraph 9 -Publisher FASB -URI https://asc.fasb.org/1943274/2147480463/815-10-45-9 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4F -Publisher FASB -URI https://asc.fasb.org/1943274/2147480434/815-10-50-4F + Details
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