Fair Value Disclosures - Difference between Fair Value and UPB for Certain Financial Instruments with Fair Value Option Elected (Details) - USD ($) $ in Millions	Sep. 30, 2025	Dec. 31, 2024
Fair Value, Option, Quantitative Disclosures [Line Items]
Held-for-sale, at fair value	$ 0	$ 11,394
Loans Held For Investment Fair Value Disclosure	7,107	2,413
Other assets and other liabilities	0	1
Held by Freddie Mac
Fair Value, Option, Quantitative Disclosures [Line Items]
Fair Value, Option, Aggregate Differences, Loans and Long-term Receivables	2	2
Debt, Fair Value	52	152
Debt, Unpaid Principal Balance, with Fair Value Option Elected	50	150
Held by consolidated trusts
Fair Value, Option, Quantitative Disclosures [Line Items]
Fair Value, Option, Aggregate Differences, Loans and Long-term Receivables	(70)	(128)
Debt, Fair Value	5,144	1,689
Debt, Unpaid Principal Balance, with Fair Value Option Elected	5,214	1,817
Interest-Only \| Held by consolidated trusts
Fair Value, Option, Quantitative Disclosures [Line Items]
Debt, Fair Value	500	500
Held-for-Sale
Fair Value, Option, Quantitative Disclosures [Line Items]
Fair Value, Option, Aggregate Differences, Loans and Long-term Receivables	0	(76)
Loans, Unpaid Principal Balance, with Fair Value Elected	0	11,470
Mortgage loans held-for-investment
Fair Value, Option, Quantitative Disclosures [Line Items]
Fair Value, Option, Aggregate Differences, Loans and Long-term Receivables	(127)	(297)
Loans, Unpaid Principal Balance, with Fair Value Elected	$ 7,234	$ 2,710

It represents loans held for investment fair value disclosure

No definition available.

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Represents Loans, Unpaid Principal Balance, with Fair Value Elected

+ References

No definition available.

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Represents unpaid principal balance of loans with fair value option elected.

+ References

No definition available.

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Represents asset and liabilities net for non-derivative purchase commitments on held-for-sale mortgage loans that are measured at fair value.

+ References

No definition available.

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This item represents the difference between the aggregate fair value and the aggregate unpaid principal balance of loans and long-term receivables (other than securities categorized as trading, available-for-sale or held-to-maturity) that have contractual principal amounts and for which the fair value option has been elected.

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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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- Definition

Fair value portion of loans held-for-sale including, but not limited to, mortgage loans and finance receivables.

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- Definition

The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

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