Debt (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended				12 Months Ended			12 Months Ended								12 Months Ended			12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2013 North America Segment [Member]	Dec. 31, 2012 North America Segment [Member]	Dec. 31, 2013 International Segment [Member] Rate	Dec. 31, 2013 Secured Debt [Member]	Dec. 31, 2012 Secured Debt [Member]	Dec. 31, 2013 Secured Debt [Member] North America Segment [Member] Rate	Dec. 31, 2012 Secured Debt [Member] North America Segment [Member] Rate	Dec. 31, 2013 Securitization Notes Payable [Member]	Dec. 31, 2012 Securitization Notes Payable [Member]	Dec. 31, 2011 Securitization Notes Payable [Member]	Dec. 31, 2013 Revolving Credit Facility [Member] International Segment [Member]	Dec. 31, 2013 Unsecured Debt [Member]	Dec. 31, 2012 Unsecured Debt [Member]	Dec. 31, 2013 Unsecured Debt [Member] International Segment [Member] Rate	Dec. 31, 2013 Senior Notes [Member] North America Segment [Member] Rate	Sep. 30, 2013 Senior Notes [Member] North America Segment [Member]	Dec. 31, 2013 Minimum [Member]	Dec. 31, 2013 Maximum [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Expiration Period																			1 year	3 years
Debt Instrument, Convertible, Remaining Discount Amortization Period																				6 years
Debt Instrument, Interest Rate, Stated Percentage Rate Range, Minimum					0.90%			1.02%	0.89%							1.09%	2.75%
Debt Instrument, Interest Rate, Stated Percentage Rate Range, Maximum					15.88%			6.07%	13.37%							12.89%	6.75%
Deferred Finance Costs, Net						$ 37	$ 31							$ 40	$ 17
Amortization of Purchase Accounting Premium										10	32	68
Purchase Price Premium, Unamortized										1
Accretion of Discount													12
Acquisition Accounting Discount - Secured Debt													47
Accretion Expense	2
Debt Instrument, Unamortized Discount	7
Unsecured debt	$ 6,973	$ 1,500	$ 4,000	$ 1,500	$ 2,973													$ 4,000