Rental Equipment (Details) (USD $) In Millions, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Property, Plant and Equipment [Line Items]
Rental equipment, net	$ 4,966	$ 2,617
Equipment Leased to Other Party [Member]
Property, Plant and Equipment [Line Items]
Rental equipment	6,820	4,209
Less accumulated depreciation	(1,854)	(1,592)
Rental equipment, net	$ 4,966	$ 2,617