Finance Receivables and Loans, Net (Schedule of Accounts, Notes, Loans and Financing Receivables) (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Accounts, Notes, Loans and Financing Receivable [Line Items]
Finance receivables and loans, net	$ 128,231	$ 129,926
Unamortized premiums and discounts and deferred fees and costs	503	587
Consumer portfolio segment
Accounts, Notes, Loans and Financing Receivable [Line Items]
Finance receivables and loans, net	89,924	87,240
Consumer portfolio segment \| Fair value \| Finance receivables and Loans, net
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans Receivable, Fair Value Disclosure	11
Consumer portfolio segment \| Automotive loan
Accounts, Notes, Loans and Financing Receivable [Line Items]
Finance receivables and loans, net	72,390	70,539
Consumer portfolio segment \| Real estate-backed loan
Accounts, Notes, Loans and Financing Receivable [Line Items]
Finance receivables and loans, net	17,322	16,701
Consumer portfolio segment \| Mortgage Finance operations
Accounts, Notes, Loans and Financing Receivable [Line Items]
Finance receivables and loans, net	16,181	15,155
Interest-only mortgage loans	$ 11	18
Interest Only Mortgage Percentage Beginning Principal Amortization Next Year	47.00%
Consumer portfolio segment \| Mortgage - Legacy
Accounts, Notes, Loans and Financing Receivable [Line Items]
Finance receivables and loans, net	$ 1,141	1,546
Interest-only mortgage loans	$ 212	341
Interest-only mortgage loans having exited the interest-only period	99.00%
Consumer portfolio segment \| Other loan
Accounts, Notes, Loans and Financing Receivable [Line Items]
Finance receivables and loans, net	$ 212	0
Commercial portfolio segment
Accounts, Notes, Loans and Financing Receivable [Line Items]
Finance receivables and loans, net	38,307	42,686
Commercial portfolio segment \| Automotive loan
Accounts, Notes, Loans and Financing Receivable [Line Items]
Finance receivables and loans, net	28,332	33,672
Commercial portfolio segment \| Real estate-backed loan
Accounts, Notes, Loans and Financing Receivable [Line Items]
Finance receivables and loans, net	4,961	4,809
Commercial portfolio segment \| Other loan
Accounts, Notes, Loans and Financing Receivable [Line Items]
Finance receivables and loans, net	$ 5,014	$ 4,205

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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Percentage of interest only loans which are expected to start amortization in the next year.

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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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- 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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-URI http://asc.fasb.org/subtopic&trid=2196772

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+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 20
-Section 45
-Paragraph 1
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