SEGMENT INFORMATION - Operating Income to Income from Continuing Operations Reconciliation (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
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Operating Income (Loss)	$ 350	$ 383	$ 391	$ 377	$ 434	$ 733	$ 811	$ 1,772	$ 1,584	$ 1,288
Interest expense, net	20	18	11	11	12	38	23	71	45	55
Other (income) expense, net	4	(21)	(33)	(38)	(6)	(17)	(44)	731	(78)	133
Income from continuing operations before income taxes	$ 326	$ 386	$ 413	$ 404	$ 428	$ 712	$ 832	970	1,617	1,100
Operating Segments
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Operating Income (Loss)								3,575	3,609	3,310
Corporate and Other
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Operating Income (Loss)								$ (1,803)	$ (2,025)	$ (2,022)