INCOME TAXES - Income Tax Expense Related To Continuing Operations (Details) - USD ($) $ in Millions	3 Months Ended					6 Months Ended		12 Months Ended
	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Jun. 30, 2018	Mar. 31, 2018	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Current
Federal								$ 8	$ 21	$ 8
State and local								3	(1)	11
International								258	308	261
Current income tax expense								269	328	280
Deferred
Federal								(140)	(228)	230
State and local								(29)	0	1
International								141	35	20
Deferred income tax expense (benefit)								(310)	(263)	211
Income tax expense (benefit)	$ 13	$ 44	$ 102	$ 63	$ 46	$ 57	$ 109	$ (41)	$ 65	$ 491