Investment Securities - Available-For-Sale Securities (Details) - USD ($) $ in Millions	Sep. 30, 2025	Dec. 31, 2024
Debt Securities, Available-for-sale [Line Items]
Amortized Cost Basis	$ 3,483	$ 3,815
Gross Unrealized Gains in Other Comprehensive Income	223	198
Gross Unrealized Losses in Other Comprehensive Income	(65)	(114)
Available-for-Sale, at fair value	3,641	3,899
Accrued Interest Receivable	10	10
Agency
Debt Securities, Available-for-sale [Line Items]
Amortized Cost Basis	3,053	3,528
Gross Unrealized Gains in Other Comprehensive Income	13	4
Gross Unrealized Losses in Other Comprehensive Income	(49)	(100)
Available-for-Sale, at fair value	3,017	3,432
Accrued Interest Receivable	6	7
Other mortgage-related securities [Member]
Debt Securities, Available-for-sale [Line Items]
Amortized Cost Basis	430	287
Gross Unrealized Gains in Other Comprehensive Income	210	194
Gross Unrealized Losses in Other Comprehensive Income	(16)	(14)
Available-for-Sale, at fair value	624	467
Accrued Interest Receivable	$ 4	$ 3

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.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
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Reference 5: http://www.xbrl.org/2003/role/disclosureRef
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Reference 6: http://www.xbrl.org/2003/role/disclosureRef
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Reference 7: http://www.xbrl.org/2003/role/disclosureRef
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+ Details

FEDERAL HOME LOAN MORTGAGE CORP 10-Q