Fair Value Measurements - Nonrecurring (Details) (Fair Value, Measurements, Nonrecurring [Member], USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
North America Segment [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financing Receivable Fair Value Disclosure	$ 54	$ 76
Fair Value, Option, Changes in Fair Value, Gain (Loss)	(14)	(23)	(32)
North America Segment [Member] | Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financing Receivable Fair Value Disclosure	0	0
North America Segment [Member] | Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financing Receivable Fair Value Disclosure	0	0
North America Segment [Member] | Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financing Receivable Fair Value Disclosure	54	76
North America Segment [Member] | Retail [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financing Receivable Fair Value Disclosure	52	70
Fair Value, Option, Changes in Fair Value, Gain (Loss)	(13)	(23)	(29)
North America Segment [Member] | Retail [Member] | Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financing Receivable Fair Value Disclosure	0	0
North America Segment [Member] | Retail [Member] | Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financing Receivable Fair Value Disclosure	0	0
North America Segment [Member] | Retail [Member] | Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financing Receivable Fair Value Disclosure	52	70
North America Segment [Member] | Dealer Loans [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financing Receivable Fair Value Disclosure	2	6
Fair Value, Option, Changes in Fair Value, Gain (Loss)	(1)	0	(3)
North America Segment [Member] | Dealer Loans [Member] | Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financing Receivable Fair Value Disclosure	0	0
North America Segment [Member] | Dealer Loans [Member] | Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financing Receivable Fair Value Disclosure	0	0
North America Segment [Member] | Dealer Loans [Member] | Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financing Receivable Fair Value Disclosure	2	6
International Segment [Member] | Retail [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financing Receivable Fair Value Disclosure	26	39
Fair Value, Option, Changes in Fair Value, Gain (Loss)	(11)	(14)	(25)
International Segment [Member] | Retail [Member] | Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financing Receivable Fair Value Disclosure	0	0
International Segment [Member] | Retail [Member] | Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financing Receivable Fair Value Disclosure	0	0
International Segment [Member] | Retail [Member] | Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financing Receivable Fair Value Disclosure	$ 26	$ 39