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Fair Value Of Financial Instruments (Realized And Unrealized Gains And Losses Included In Earnings Pertaining To Level 3 Assets And Liabilities) (Detail) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2022 | Sep. 30, 2021 | Sep. 30, 2022 | Sep. 30, 2021
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |  |  |
Net gains (losses) on financial instruments at fair value and foreign exchange | $ 25 | $ 9 | $ 51 | $ 41
Variable Interest Entity Primary Beneficiary [Member] |  |  |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |  |  |
Net gains (losses) on financial instruments at fair value and foreign exchange | (36) | 4 | (16) | (10)
Fair Value Inputs Level 3 [Member] | Total Gains (Losses) Included in Earnings [Member] |  |  |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |  |  |
Net gains (losses) on financial instruments at fair value and foreign exchange | 8 | 4 | 29 | 13
Total revenues | (26) | 7 | 17 | 0
Fair Value Inputs Level 3 [Member] | Change in Unrealized Gains (Losses) for the Period Included in Earnings for Assets and Liabilities still held [Member] |  |  |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |  |  |
Net gains (losses) on financial instruments at fair value and foreign exchange | 8 | 4 | 28 | 13
Total revenues | 7 | 8 | 27 | 15
Fair Value Inputs Level 3 [Member] | Variable Interest Entity Primary Beneficiary [Member] | Total Gains (Losses) Included in Earnings [Member] |  |  |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |  |  |
Net gains (losses) on financial instruments at fair value and foreign exchange | (34) | 3 | (12) | (13)
Fair Value Inputs Level 3 [Member] | Variable Interest Entity Primary Beneficiary [Member] | Change in Unrealized Gains (Losses) for the Period Included in Earnings for Assets and Liabilities still held [Member] |  |  |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |  |  |
Net gains (losses) on financial instruments at fair value and foreign exchange | $ (1) | $ 4 | $ (1) | $ 2

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- Definition Amount of gain (loss) recognized in income from asset and liability measured at fair value on recurring basis using unobservable input (level 3). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(1) -URI https://asc.fasb.org/extlink&oid=126976982&loc=d3e19207-110258 + Details
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