Supplemental Cash Flow Information (Details) - USD ($) shares in Millions, $ in Millions		12 Months Ended
	Dec. 09, 2016	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Changes in operating assets and liabilities
Decrease in accounts receivable		$ 350	$ 742	$ 63
Increase in other current assets		(29)	(177)	(164)
(Increase) decrease in other assets		(12)	5	12
Decrease in accounts payable and other current liabilities		(286)	(828)	(884)
Decrease in other long-term liabilities		(55)	(72)	(71)
Change in income taxes receivable / payable, net		(133)	(65)	(31)
Net change in operating assets and liabilities		(165)	(395)	(1,075)
Certain cash operating activities
Cash payments for interest		351	439	490
Cash payments for income taxes		172	314	329
Non-cash investing and financing activities
Capital additions, accrued at end of period		42	$ 128	$ 139
Issuance of shares for acquisition of noncontrolling interest		$ 317
Issuance of shares for acquisition of noncontrolling interest (in shares)	23.8