Related Party Transactions (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2017	Mar. 31, 2016	Dec. 31, 2016
Related Party Transaction [Line Items]
Advances drawn on lines of credit due from GM	$ 617		$ 510
Affiliated Entity [Member]
Related Party Transaction [Line Items]
Finance receivables, net due	128		0
Advances drawn on lines of credit due from GM	145		137
Subvention receivable	471		373
Leased vehicle subvention earned	709	$ 459
Affiliated Entity [Member] \| Retail Finance Receivables [Member]
Related Party Transaction [Line Items]
Interest subvention earned	111	103
Affiliated Entity [Member] \| Commercial Finance Receivables [Member]
Related Party Transaction [Line Items]
Finance receivables, net due	339		401
Commercial loan funding payable	438		$ 389
Interest subvention earned	40	40
Parent Company [Member]
Related Party Transaction [Line Items]
Revenue from related parties	$ 1,000	$ 1,200

Related Party, Leased Vehicle Income Earned

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- Definition

For an unclassified balance sheet, amounts due from related parties including affiliates, employees, joint ventures, officers and stockholders, immediate families thereof, and pension funds.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Amount of interest income earned from interest-bearing assets owed to the entity by related party.

+ References

No definition available.

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- Definition

The amount for notes payable (written promise to pay), due to related parties.

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- Definition

Net amount of the investment in a contractual right to receive money on demand or on fixed or determinable dates that is recognized as an asset in the creditor's statement of financial position. Examples include, but are not limited to, credit card receivables, notes receivable and receivables relating to lessor's rights to payments from leases other than operating leases that have been recorded as assets. Excludes trade accounts receivable with contractual maturity of one year or less and arose from the sale of goods or services.

+ References

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- Definition

For an unclassified balance sheet, amounts due from parties associated with the reporting entity as evidenced by a written promise to pay.

+ References

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Amount of revenue, fees and commissions earned from transactions between (a) a parent company and its subsidiaries; (b) subsidiaries of a common parent; (c) an entity and trusts for the benefit of employees, for example, but not limited to, pension and profit-sharing trusts that are managed by or under the trusteeship of the entity's management; (d) an entity and its principal, owners, management, or members of their immediate families; and (e) affiliates.

+ References

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