Investment Securities - Trading Securities (Details) - USD ($) $ in Millions	Sep. 30, 2026	Dec. 31, 2025
Trading Securities [Line Items]
Total fair value of trading securities	$ 76,009	$ 82,096
Mortage-related securities
Trading Securities [Line Items]
Total fair value of trading securities	10,781	10,932
Non-mortgage-related securities
Trading Securities [Line Items]
Total fair value of trading securities	$ 65,228	$ 71,164

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.

- Definition

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