Guarantees (Details) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014
Product Warranty Liability [Line Items]
Product Warranty Accrual, Warranties Issued	$ 208	$ 180
Balance as of January 1	1,264	1,324
Settlements made	217	242
Other	(56)	(33)
Balance as of September 30	1,199	1,229
Discontinued Operations, Held-for-sale [Member]
Product Warranty Liability [Line Items]
Balance as of September 30	$ 42	$ 38