Guarantees (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Product Warranty Liability [Line Items]
Balance as of January 1	$ 1,199	$ 1,212
Warranties and performance guarantees issued	78	76
Settlements made	56	62
Other	1	10
Balance as of March 31	$ 1,222	$ 1,236