Finance Receivables - Delinquency (Details) - Consumer Finance Receivables [Member] - Automobile Loan [Member] - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Financing Receivable, Recorded Investment, Past Due [Line Items]
In repossession	$ 46	$ 40
In repossession of contractual amount due (percent)	0.20%	0.20%
Financing receivable and in repossession past due	$ 1,764	$ 1,555
Financing receivable and in repossession past due (percent)	6.00%	6.10%
31 to 60 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivable past due	$ 1,237	$ 1,083
Financing receivable past due (percent)	4.20%	4.20%
Greater Than 60 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivable past due	$ 481	$ 432
Financing receivable past due (percent)	1.60%	1.70%
30 or More Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivable past due	$ 1,718	$ 1,515
Financing receivable past due (percent)	5.80%	5.90%
North America [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
In repossession	$ 42	$ 36
Financing receivable and in repossession past due	1,581	1,358
North America [Member] | 31 to 60 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivable past due	1,150	994
North America [Member] | Greater Than 60 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivable past due	389	328
North America [Member] | 30 or More Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivable past due	1,539	1,322
International [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
In repossession	4	4
Financing receivable and in repossession past due	183	197
International [Member] | 31 to 60 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivable past due	87	89
International [Member] | Greater Than 60 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivable past due	92	104
International [Member] | 30 or More Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivable past due	$ 179	$ 193