Fair Value Option - Gains and Losses on Other Financial Assets and Financial Liabilities at Fair Value (Detail) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2026	Mar. 31, 2025
Fair Value, Option, Quantitative Disclosures [Line Items]
Fair value option gains/(losses)	$ 2,358	$ (1,072)
Unsecured short-term borrowings
Fair Value, Option, Quantitative Disclosures [Line Items]
Fair value option gains/(losses)	1,376	417
Unsecured long-term borrowings
Fair Value, Option, Quantitative Disclosures [Line Items]
Fair value option gains/(losses)	645	(1,284)
Other
Fair Value, Option, Quantitative Disclosures [Line Items]
Fair value option gains/(losses)	$ 337	$ (205)

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.

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