CONDENSED CONSOLIDATED BALANCE SHEETS (PARENTHETICAL) - USD ($) $ in Millions		Sep. 30, 2018	Dec. 31, 2017
Statement of Financial Position [Abstract]
Allowance for doubtful accounts	[1]	$ 567	$ 584
Property, plant and equipment, accumulated depreciation	[1]	17,078	16,172
Current portion of long-term debt	[1]	$ 4,255	$ 3,546

[1] Amounts may not add due to rounding.