Fair Value Measurement - Fair Value of Financial Instruments (Details) - USD ($) $ in Millions	Mar. 31, 2025	Dec. 31, 2024
Financial assets:
Loans held for sale	$ 285	$ 87
Level 1
Financial assets:
Cash and cash equivalents	4,108	3,028
Restricted cash for securitization investors	392	441
Net loans held for investment	0	0
Loans held for sale	0	0
Interest receivable	0	0
Other investments	0	0
Financial liabilities:
Deposits with defined maturities	0	0
Securitized debt obligations	0	0
Senior and subordinated notes	0	0
Federal funds purchased and securities loaned or sold under agreements to repurchase	0	0
Interest payable	0	0
Level 2
Financial assets:
Cash and cash equivalents	44,465	40,202
Restricted cash for securitization investors	0	0
Net loans held for investment	0	0
Loans held for sale	387	115
Interest receivable	2,599	2,532
Other investments	1,330	1,329
Financial liabilities:
Deposits with defined maturities	68,955	79,091
Securitized debt obligations	11,764	14,335
Senior and subordinated notes	30,124	31,636
Federal funds purchased and securities loaned or sold under agreements to repurchase	573	562
Interest payable	646	666
Level 3
Financial assets:
Cash and cash equivalents	0	0
Restricted cash for securitization investors	0	0
Net loans held for investment	313,467	316,467
Loans held for sale	14	0
Interest receivable	0	0
Other investments	0	0
Financial liabilities:
Deposits with defined maturities	0	0
Securitized debt obligations	0	0
Senior and subordinated notes	0	0
Federal funds purchased and securities loaned or sold under agreements to repurchase	0	0
Interest payable	0	0
Carrying Value
Financial assets:
Cash and cash equivalents	48,573	43,230
Restricted cash for securitization investors	392	441
Net loans held for investment	307,699	311,517
Loans held for sale	401	115
Interest receivable	2,599	2,532
Other investments	1,330	1,329
Financial liabilities:
Deposits with defined maturities	68,851	78,944
Securitized debt obligations	11,716	14,264
Senior and subordinated notes	29,459	30,696
Federal funds purchased and securities loaned or sold under agreements to repurchase	573	562
Interest payable	646	666
Estimated Fair Value
Financial assets:
Cash and cash equivalents	48,573	43,230
Restricted cash for securitization investors	392	441
Net loans held for investment	313,467	316,467
Loans held for sale	401	115
Interest receivable	2,599	2,532
Other investments	1,330	1,329
Financial liabilities:
Deposits with defined maturities	68,955	79,091
Securitized debt obligations	11,764	14,335
Senior and subordinated notes	30,124	31,636
Federal funds purchased and securities loaned or sold under agreements to repurchase	573	562
Interest payable	$ 646	$ 666

Deposits with Defined Maturities, Fair Value Disclosure

No definition available.

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- Definition

This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure and may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. This item represents accrued interest payable on all forms of debt, including trade payables, that has been incurred and is unpaid as of the balance sheet date.

+ References

No definition available.

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- Definition

This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure and may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. This item represents interest earned but not received as of the balance sheet date.

+ References

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- Definition

Restricted Cash and Cash Equivalents, Fair value Disclosure

+ References

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- Definition

Secured Debt, Fair Value Disclosure

+ References

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- Definition

Unsecured Debt, Fair Value Disclosure

+ References

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- Definition

Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

+ References

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- Definition

Fair value portion of short term borrowing where a bank borrows, at the federal funds rate, from another bank and securities that an entity sells and agrees to repurchase at a specified date for a specified price.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2E
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-2E

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-2

Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-2

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- References

No definition available.

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- References

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- Definition

Fair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method.

+ References

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (bbb)(2)(i)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-2

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (bbb)(2)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-2

Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (bbb)(1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-2

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-2

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-2

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- Definition

Fair value portion of loan receivable, including, but not limited to, mortgage loans held for investment, finance receivables held for investment, policy loans on insurance contracts.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 825
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 10
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482907/825-10-50-10

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