Finance Receivables - Troubled Debt Restructurings (Details) - North America Segment [Member] - Automobile Loan [Member] $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2016 USD ($) loan	Sep. 30, 2015 USD ($) loan	Sep. 30, 2016 USD ($) loan	Sep. 30, 2015 USD ($) loan	Dec. 31, 2015 USD ($)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Outstanding recorded investment	$ 1,837		$ 1,837		$ 1,612
Less: allowance for loan losses	(256)		(256)		(220)
Outstanding recorded investment, net of allowance	1,581		1,581		1,392
Unpaid principal balance	1,884		1,884		$ 1,642
Average outstanding recorded investment	1,785	$ 1,403	1,725	$ 1,361
Finance charge income recognized	$ 55	$ 41	$ 156	$ 122
Number of loans classified as TDRs during the period \| loan	18,548	16,122	49,327	42,246
Recorded investment of loans classified as TDRs during the period	$ 315	$ 270	$ 846	$ 716

Troubled Debt Restructurings - Number of Loans Entering a Modification Program

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Amount of allowance for credit losses related to receivables which had been measured under a general allowance for credit losses methodology that are now identified as troubled debt restructurings.

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No definition available.

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Pre-modification amount of investment in financing receivables modified by troubled debt restructurings.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
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The amount of the outstanding recorded investment related to financing receivables that have been modified by troubled debt restructurings.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
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Average amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Amount of unpaid principal balance of impaired financing receivables with related allowance for credit losses and without related allowance for credit losses.

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The gross interest income that would have been recorded in the period on troubled debt restructurings, if the loans had been current in accordance with their original terms and had been outstanding throughout the period or since origination, if held for part of the period.

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Amount of receivables for which the allowance for credit losses had previously been measured under a general allowance for credit losses methodology, and are now identified as troubled debt restructurings.

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