INCOME TAXES - Provision for Income Taxes (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Current
-U.S. Federal	$ (1,253)	$ (203)	$ (167)
-U.S. State	(152)	(41)	(40)
-Non-U.S.	(178)	(56)	(50)
Current income tax expense	(1,583)	(300)	(257)
Deferred
-U.S. Federal	107	(61)	(131)
-U.S. State	(26)	(14)	(7)
-Non-U.S.	38	(29)	(1)
Deferred income tax expense	119	(104)	(139)
Provision for income taxes	$ (1,464)	$ (404)	$ (396)