Supplemental Cash Flow Information (Details) - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016
Supplemental Cash Flow Information
Interest paid in cash	$ 145	$ 136
Income taxes paid in cash (all non-US)	89	75
Interest paid for note repurchase premiums related to debt repaid prior to maturity	16
Amount of receivables sold	$ 205	$ 300