Investment Securities - Investment Securities (Details) - USD ($) $ in Millions	Dec. 31, 2025	Dec. 31, 2024
Investments, Debt and Equity Securities [Abstract]
Trading securities	$ 82,096	$ 51,872
Available-for-sale securities, at fair value	3,316	3,899
Total fair value of investment securities	$ 85,412	$ 55,771

Amount of investment in debt security measured at fair value with change in fair value recognized in net income (trading).

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+ Details