DEBT AND FINANCING COSTS - Components of Financing Costs, Net (Details) - USD ($) $ in Millions	1 Months Ended	12 Months Ended
	Jan. 31, 2017	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Debt Disclosure [Abstract]
Interest expense		$ 430	$ 441	$ 457
Amortization of debt issuance costs		7	9	9
Capitalized interest		(37)	(44)	(51)
Loss on extinguishment of debt	$ 1	75	94	1
Interest income		(13)	(22)	(19)
Financing costs, net		$ 462	$ 478	$ 397