Finance Receivables - Narrative (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2014 portfolio	Dec. 31, 2013	Dec. 31, 2012
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number Of Portfolios	2acf_NumberOfPortfolios
Financing Receivable, Recorded Investment, Nonaccrual Status	$ 682	$ 642
Troubled Debt Restructurings - Subsequent Default	25	22	4
Pre-Acquisition Portfolio [Member] \| Consumer Finance Receivables [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Transfer from non-accretable difference	52	74
Pre-Acquisition Portfolio [Member] \| Consumer Finance Receivables [Member] \| North America Segment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Transfer from non-accretable difference	$ 46	$ 55	$ 170

The number of portfolio in a specified class of financing receivables.

No definition available.

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- Definition

Troubled Debt Restructurings - Subsequent Default

+ References

No definition available.

+ Details

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- Details

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- Definition

Amount of increase of reclassification from nonaccretable difference to the excess of a loan's cash flows expected to be collected over the investor's initial investment in acquired loans not accounted for as debt securities with evidence of deterioration of credit quality.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 30

-Section 15

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=27045933&loc=d3e13503-111538

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 30

-Section 50

-Paragraph 2

-Subparagraph (a)(2)

-URI http://asc.fasb.org/extlink&oid=6379141&loc=d3e15032-111544

+ Details

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- Definition

Recorded investment in financing receivables that are on nonaccrual status as of the balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 7

-Subparagraph (d)

-URI http://asc.fasb.org/extlink&oid=35738203&loc=d3e5111-111524

+ Details

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- Details

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