Related Party Transactions - Related Party Payables (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Related Party Transaction [Line Items]
Advances drawn on lines of credit due from GM	$ 510	$ 573
Affiliated Entity [Member]
Related Party Transaction [Line Items]
Advances drawn on lines of credit due from GM	137	190
Subvention receivable	373	383
Leased vehicle subvention earned	2,238	1,001	$ 311
Affiliated Entity [Member] \| Retail Finance Receivables [Member]
Related Party Transaction [Line Items]
Interest subvention earned	443	313	248
Affiliated Entity [Member] \| Commercial Finance Receivables [Member]
Related Party Transaction [Line Items]
Commercial finance receivables, net due from dealers consolidated by GM	401	229
Commercial loan funding payable	389	351
Interest subvention earned	169	175	195
Parent Company [Member]
Related Party Transaction [Line Items]
Revenue from related parties	$ 4,400	$ 3,600	$ 1,200

Related Party, Leased Vehicle Income Earned

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

+ References

No definition available.

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

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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.

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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.

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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.

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