SUPPLEMENTAL FINANCIAL STATEMENT INFORMATION Interest Income and Expense (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Supplemental Income Statement Elements [Abstract]
Interest expense	$ 184	$ 198	$ 547	$ 571
Interest income	51	46	146	140
Capitalized interest costs	$ 9	$ 6	$ 26	$ 18