Mortgage Loans Held for Sale - Activities of Mortgage Loans Held for Sale (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022
Loans Receivable Held-for-sale, Net, Reconciliation to Cash Flow [Roll Forward]
Balance - beginning of year	$ 893	$ 4,381
Loans sold and loan payments received	(14,097)	(34,731)
Mortgage loans originated and purchased, net of fees	12,856	28,309
Repurchase of loans out of Ginnie Mae securitizations(1)	1,234	3,067
Net change in unrealized gain (loss) on retained loans held for sale	44	(132)
Net transfers of mortgage loans held for sale(2)	(3)	(1)
Balance - end of year	$ 927	$ 893

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

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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.

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-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//1943274/2147481852/948-310-45-1

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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 bad debt, of additions to loan receivables held-for-sale that are not part of a disposal group.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-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

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- Definition

Amount, after allowance for bad debt, of deductions to loan receivables held-for-sale that are not part of a disposal group.

+ References

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