EMPLOYEE BENEFIT PLANS (Schedule of Assumptions Used in Calculating Projected Benefit Cost and Net Periodic Benefit Cost) (Details)	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Defined Benefit Plan Disclosure [Line Items]
Expected return on plan assets	10.00%
Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Discount rate	4.35%	3.64%	4.11%
Rate of future compensation increases	3.90%	3.90%	4.00%
Expected return on plan assets	6.00%	6.20%	5.30%
PBOP Plans
Defined Benefit Plan Disclosure [Line Items]
Rate of future compensation increases	0.00%	0.00%	0.00%
PBOP Plans | Minimum
Defined Benefit Plan Disclosure [Line Items]
Discount rate	4.29%	3.60%	4.05%
Expected return on plan assets	3.60%	3.30%	2.80%
PBOP Plans | Maximum
Defined Benefit Plan Disclosure [Line Items]
Discount rate	4.37%	3.67%	4.19%
Expected return on plan assets	6.80%	7.10%	6.00%