Fair Value Measurements - Information about Fair Value Measurements using Significant Unobservable Inputs (Details) (Level 3 [Member], Fair Value, Measurements, Nonrecurring [Member], USD $) In Millions, unless otherwise specified	Jun. 30, 2013	Dec. 31, 2012
North America Segment [Member]
Fair Value Inputs Quantitative Information [Line Items]
Financing Receivable Fair Value Disclosure	$ 41	$ 54
Retail [Member] | North America Segment [Member]
Fair Value Inputs Quantitative Information [Line Items]
Financing Receivable Fair Value Disclosure	41	52
Retail [Member] | North America Segment [Member] | Income Approach Valuation Technique [Member]
Fair Value Inputs Quantitative Information [Line Items]
Financing Receivable Fair Value Disclosure	41	52
Retail [Member] | North America Segment [Member] | Income Approach Valuation Technique [Member] | Minimum [Member]
Fair Value Inputs Quantitative Information [Line Items]
Financing Receivable Fair Value Disclosure	28	38
Retail [Member] | North America Segment [Member] | Income Approach Valuation Technique [Member] | Maximum [Member]
Fair Value Inputs Quantitative Information [Line Items]
Financing Receivable Fair Value Disclosure	41	52
Retail [Member] | International Segment [Member]
Fair Value Inputs Quantitative Information [Line Items]
Financing Receivable Fair Value Disclosure	23	26
Retail [Member] | International Segment [Member] | Income Approach Valuation Technique [Member]
Fair Value Inputs Quantitative Information [Line Items]
Financing Receivable Fair Value Disclosure	23	26
Retail [Member] | International Segment [Member] | Income Approach Valuation Technique [Member] | Minimum [Member]
Fair Value Inputs Quantitative Information [Line Items]
Financing Receivable Fair Value Disclosure	21	25
Retail [Member] | International Segment [Member] | Income Approach Valuation Technique [Member] | Maximum [Member]
Fair Value Inputs Quantitative Information [Line Items]
Financing Receivable Fair Value Disclosure	25	27
Dealer Loans [Member] | North America Segment [Member]
Fair Value Inputs Quantitative Information [Line Items]
Financing Receivable Fair Value Disclosure	0	2
Dealer Loans [Member] | North America Segment [Member] | Income Approach Valuation Technique [Member]
Fair Value Inputs Quantitative Information [Line Items]
Financing Receivable Fair Value Disclosure	0	2
Dealer Loans [Member] | North America Segment [Member] | Income Approach Valuation Technique [Member] | Minimum [Member]
Fair Value Inputs Quantitative Information [Line Items]
Financing Receivable Fair Value Disclosure	0	1
Dealer Loans [Member] | North America Segment [Member] | Income Approach Valuation Technique [Member] | Maximum [Member]
Fair Value Inputs Quantitative Information [Line Items]
Financing Receivable Fair Value Disclosure	$ 0	$ 3