Finance Receivables and Loans, Net (Schedule of Accounts, Notes, Loans and Financing Receivables) (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Accounts, Notes, Loans and Financing Receivable [Line Items]
Finance receivables and loans, net	$ 118,534	$ 128,231
Unamortized premiums and discounts and deferred fees and costs	2,000
Consumer portfolio segment
Accounts, Notes, Loans and Financing Receivable [Line Items]
Finance receivables and loans, net	89,202	89,924
Consumer portfolio segment \| Automotive loan
Accounts, Notes, Loans and Financing Receivable [Line Items]
Finance receivables and loans, net	73,668	72,390
Consumer portfolio segment \| Real estate-backed loan
Accounts, Notes, Loans and Financing Receivable [Line Items]
Finance receivables and loans, net	15,127	17,322
Consumer portfolio segment \| Mortgage Finance operations
Accounts, Notes, Loans and Financing Receivable [Line Items]
Finance receivables and loans, net	14,632	16,181
Interest-only mortgage loans	8	11
Consumer portfolio segment \| Mortgage - Legacy
Accounts, Notes, Loans and Financing Receivable [Line Items]
Finance receivables and loans, net	495	1,141
Interest-only mortgage loans	$ 30	212
Interest-only mortgage loans having exited the interest-only period	99000000.00%
Consumer portfolio segment \| Other loan
Accounts, Notes, Loans and Financing Receivable [Line Items]
Finance receivables and loans, net	$ 407	212
Loans receivable, fair value	8	11
Commercial portfolio segment
Accounts, Notes, Loans and Financing Receivable [Line Items]
Finance receivables and loans, net	29,332	38,307
Commercial portfolio segment \| Automotive loan
Accounts, Notes, Loans and Financing Receivable [Line Items]
Finance receivables and loans, net	19,082	28,332
Commercial portfolio segment \| Real estate-backed loan
Accounts, Notes, Loans and Financing Receivable [Line Items]
Finance receivables and loans, net	5,008	4,961
Commercial portfolio segment \| Other loan
Accounts, Notes, Loans and Financing Receivable [Line Items]
Finance receivables and loans, net	5,242	5,014
Finance receivables and loans, net
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accrued interest receivable	$ 587	$ 488

Held For Investment Mortgage Finance Receivables Exited Interest Only Mortgage Loans

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- Definition

Held for investment mortgage finance receivables interest only mortgage loans.

+ References

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Carrying amount as of the balance sheet date of current interest earned but not received. Also called accrued interest or accrued interest receivable. For classified balance sheets, represents the current amount receivable, that is amounts expected to be collected within one year or the normal operating cycle, if longer.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
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Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 2
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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

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-Publisher FASB
-Name Accounting Standards Codification
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