Variable Interest Entities - VIEs of Which we are the Primary Beneficiary (Details) (USD $)	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Assets and liabilities [Abstract]
Cash and cash equivalents	$ 15,659,000,000	$ 17,148,000,000	$ 14,805,000,000	$ 20,894,000,000
Debt	105,058,000,000	99,488,000,000
Derivative Instruments related exposure [Abstract]
Fair Value of Assets	1,500,000,000
Financial Performance [Abstract]
Interest expense	3,828,000,000	4,431,000,000	6,152,000,000
Variable Interest Entity, Primary Beneficiary [Member]
Assets and liabilities [Abstract]
Cash and cash equivalents	2,911,000,000	3,402,000,000
Debt	40,245,000,000	41,421,000,000
Variable Interest Entity, Primary Beneficiary [Member] | Net Investment in Operating Leases [Member]
Assets and liabilities [Abstract]
Cash and cash equivalents	400,000,000	400,000,000
Finance Receivables Net And Net Investment In Operating Leases	6,300,000,000	6,400,000,000
Financial Services [Member]
Assets and liabilities [Abstract]
Cash and cash equivalents	9,412,000,000	9,183,000,000	8,504,000,000	11,132,000,000
Debt	90,802,000,000	86,595,000,000
Derivative Instruments related exposure [Abstract]
Fair Value of Assets	1,300,000,000	1,375,000,000
Fair Value of Liabilities	381,000,000	299,000,000
Financial Performance [Abstract]
Interest expense	3,115,000,000	3,614,000,000	4,345,000,000
Financial Services [Member] | Finance Receivables [Member]
Assets and liabilities [Abstract]
Cash and cash equivalents	100,000,000	300,000,000
Finance Receivables Net And Net Investment In Operating Leases	3,500,000,000	6,200,000,000
Financial Services [Member] | Variable Interest Entity, Primary Beneficiary [Member]
Variable Interest Entity [Line Items]
Cash contribution for collateral to support Wholesale Securitization Program	0	0
Assets and liabilities [Abstract]
Cash and cash equivalents	2,900,000,000	3,400,000,000
Finance Receivables Net And Net Investment In Operating Leases	53,800,000,000	56,200,000,000
Debt	40,200,000,000	41,400,000,000
Footnote information [Abstract]
Variable Interest Entities Liabilities Excluded	145,000,000	246,000,000
Financial Services [Member] | Variable Interest Entity, Primary Beneficiary [Member] | Finance Receivables [Member]
Assets and liabilities [Abstract]
Cash and cash equivalents	2,500,000,000	3,000,000,000
Finance Receivables Net And Net Investment In Operating Leases	47,500,000,000	49,800,000,000
Debt	36,000,000,000	37,200,000,000
Financial Services [Member] | Variable Interest Entity, Primary Beneficiary [Member] | Retail [Member]
Assets and liabilities [Abstract]
Cash and cash equivalents	2,200,000,000	2,500,000,000
Finance Receivables Net And Net Investment In Operating Leases	27,000,000,000	31,900,000,000
Debt	23,200,000,000	26,000,000,000
Financial Services [Member] | Variable Interest Entity, Primary Beneficiary [Member] | Wholesale [Member]
Assets and liabilities [Abstract]
Cash and cash equivalents	300,000,000	500,000,000
Finance Receivables Net And Net Investment In Operating Leases	20,500,000,000	17,900,000,000
Debt	12,800,000,000	11,200,000,000
Financial Services [Member] | Variable Interest Entity, Primary Beneficiary [Member] | Net Investment in Operating Leases [Member]
Assets and liabilities [Abstract]
Cash and cash equivalents	400,000,000	400,000,000
Finance Receivables Net And Net Investment In Operating Leases	6,300,000,000	6,400,000,000
Debt	4,200,000,000	4,200,000,000
Minimum [Member] | Financial Services [Member] | Variable Interest Entity, Primary Beneficiary [Member]
Variable Interest Entity [Line Items]
Cash contribution for collateral to support Wholesale Securitization Program	0	0
Maximum [Member] | Financial Services [Member] | Variable Interest Entity, Primary Beneficiary [Member]
Variable Interest Entity [Line Items]
Cash contribution for collateral to support Wholesale Securitization Program	373,000,000	490,000,000
Securitization Transactions [Member] | Financial Services [Member]
Derivative Instruments related exposure [Abstract]
Fair Value of Assets	78,000,000	238,000,000
Fair Value of Liabilities	197,000,000	160,000,000
Financial Performance [Abstract]
Derivative expense/(income)	222,000,000	42,000,000	152,000,000
Securitization Transactions [Member] | Financial Services [Member] | Related to the VIEs [Member]
Derivative Instruments related exposure [Abstract]
Fair Value of Assets	74,000,000	81,000,000
Fair Value of Liabilities	63,000,000	63,000,000
Financial Performance [Abstract]
Derivative expense/(income)	(5,000,000)	11,000,000	(73,000,000)
Securitization Transactions [Member] | Financial Services [Member] | Variable Interest Entity, Primary Beneficiary [Member]
Financial Performance [Abstract]
Interest expense	760,000,000	994,000,000	1,247,000,000
Securitization Transactions [Member] | Financial Services [Member] | Variable Interest Entity, Primary Beneficiary [Member] | VIEs [Member]
Derivative Instruments related exposure [Abstract]
Fair Value of Assets	4,000,000	157,000,000
Fair Value of Liabilities	134,000,000	97,000,000
Financial Performance [Abstract]
Derivative expense/(income)	$ 227,000,000	$ 31,000,000	$ 225,000,000