Mortgage Loans Held for Sale - Activities of Mortgage Loans Held for Sale (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2024	Dec. 31, 2023
Loans Receivable Held-for-sale, Net, Reconciliation to Cash Flow [Roll Forward]
Balance - beginning of year	$ 927	$ 893
Loans sold and loan payments received	(23,412)	(14,097)
Mortgage loans originated and purchased, net of fees	23,022	12,856
Repurchase of loans out of Ginnie Mae securitizations(1)	1,670	1,234
Net change in unrealized gain on retained loans held for sale	5	44
Net transfers of mortgage loans held for sale(2)	(1)	(3)
Balance - end of year	$ 2,211	$ 927

Loans Receivable Held-for-sale, Reconciliation to Cash Flow, Transfer from(to) Other Assets

No definition available.

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- Definition

Loans Receivable Held-for-sale, Reconciliation to Cash Flow, Changes in Fair Value

+ References

No definition available.

+ Details

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- Definition

Repurchase of Ginnie Mae Receivables

+ References

No definition available.

+ Details

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- Definition

Amount, before valuation allowance, of financing receivable classified as held-for-sale.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481990/310-10-45-2

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 948
-SubTopic 310
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477011/948-310-45-1

+ Details

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

+ Details

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- Definition

Amount, after allowance for credit loss, of addition to financing receivable held for sale that is not part of disposal group.

+ References

+ Details

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- Definition

Amount, after allowance for credit loss, of deduction to financing receivable held for sale that is not part of disposal group.

+ References

+ Details

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