Investments in Securities - Trading 1 (Details) - USD ($) $ in Millions	Mar. 31, 2025	Dec. 31, 2024
Schedule of Investments in Trading Securities [Line Items]
Trading, at fair value	$ 78,902	$ 78,728
Amortized cost	470	487
Available-for-sale securities	445	469
Total investments in securities	79,347	79,197
Mortgage-related securities
Schedule of Investments in Trading Securities [Line Items]
Trading, at fair value	1,018	1,098
Non-mortgage-related securities
Schedule of Investments in Trading Securities [Line Items]
Trading, at fair value	77,884	77,630
Non-mortgage-related securities \| Pledged as collateral
Schedule of Investments in Trading Securities [Line Items]
Trading, at fair value	9,400	8,900
Consolidated trusts \| Mortgage-related securities
Schedule of Investments in Trading Securities [Line Items]
Trading, at fair value	$ 289	$ 300

Amount, after allowance for credit loss, of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), investment in debt security measured at amortized cost (held-to-maturity), and investment in debt security measured at fair value with change in fair value recognized in net income (trading).

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