Fair Value Measurements Fair Value, Assets Measured on Nonrecurring Basis Using Unobservable Inputs (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Fair Value, Assets and Liabilities Measured on Nonrecurring Basis [Line Items]
Nonrecurring fair value losses	$ (90)	$ (167)	$ (229)
Fair Value Measurements Nonrecurring [Member] | Operating Lease Equipment [Member]
Fair Value, Assets and Liabilities Measured on Nonrecurring Basis [Line Items]
Nonrecurring fair value losses	(52)	(159)
Fair Value Measurements Nonrecurring [Member] | Property, Plant and Equipment [Member]
Fair Value, Assets and Liabilities Measured on Nonrecurring Basis [Line Items]
Nonrecurring fair value losses	(9)	(6)
Fair Value Measurements Nonrecurring [Member] | Other assets and Acquired intangible assets [Member]
Fair Value, Assets and Liabilities Measured on Nonrecurring Basis [Line Items]
Nonrecurring fair value losses	(10)
Fair Value Measurements Nonrecurring [Member] | Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Nonrecurring Basis [Line Items]
Total Fair Value	106	278
Nonrecurring fair value losses	(71)	(165)
Fair Value Measurements Nonrecurring [Member] | Level 3 [Member] | Market Approach Valuation Technique [Member]
Fair Value, Assets and Liabilities Measured on Nonrecurring Basis [Line Items]
Operating Lease Equipment, Fair Value	84	270
Fair Value Measurements Nonrecurring [Member] | Level 3 [Member] | Income Approach Valuation Technique [Member]
Fair Value, Assets and Liabilities Measured on Nonrecurring Basis [Line Items]
Property, Plant, and Equipment, Fair Value	10	8
Other assets and Acquired intangible assets, Fair Value	$ 12