EMPLOYEE BENEFIT PLANS (Change in Projected Benefit Obligation and Plan Assets and Reconciliation of Funded Status) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Pension Benefits
Change in Projected Benefit Obligation
Beginning of Period	$ 475	$ 424
Actuarial (Gain) Loss	(42)	42
Interest Cost	16	15	$ 15
Service Cost	15	13	12
Benefits Paid	(23)	(19)
Plan Amendments	(1)	0
End of Period	440	475	424
Change in Fair Value of Plan Assets
Beginning of Period	403	354
Actual Return on Plan Assets	(25)	59
Benefits Paid	(23)	(19)
Employer Contributions	21	9
End of Period	376	403	354
Funded Status at End of Period	(64)	(72)
Other Postretirement Benefits
Change in Projected Benefit Obligation
Beginning of Period	82	79
Actuarial (Gain) Loss	(8)	1
Interest Cost	2	2	2
Service Cost	5	4	4
Benefits Paid	(5)	(4)
Plan Amendments	(2)	0
End of Period	74	82	79
Change in Fair Value of Plan Assets
Beginning of Period	17	14
Actual Return on Plan Assets	(1)	2
Benefits Paid	(5)	(4)
Employer Contributions	6	5
End of Period	17	17	$ 14
Funded Status at End of Period	$ (57)	$ (65)