PENSION AND OTHER POSTRETIREMENT BENEFIT PLANS (Plan Assumptions) (Detail)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Pension Plan [Member]
DefinedBenefitPlanWeightedAverageAssumptionsUsedInCalculatingBenefitObligationAbstract
Discount rate	2.36%	3.05%
Rate Of Compensation Increase	3.41%	3.46%
DefinedBenefitPlanWeightedAverageAssumptionsUsedInCalculatingNetPeriodicBenefitCostAbstract
Discount Rate	3.05%	4.09%
Expected return on assets assumption	7.11%	7.59%
Net Periodic Benefit Cost Rate Of Compensation Increase	3.46%	3.50%
Other Postretirement Benefits Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Year That Rate Reaches Ultimate Trend Rate	2026	2026
DefinedBenefitPlanWeightedAverageAssumptionsUsedInCalculatingBenefitObligationAbstract
Discount rate	2.43%	3.15%
DefinedBenefitPlanAssumedHealthCareCostTrendRatesAbstract
Rate Assumed For Next Fiscal Year	7.25%	7.50%
Ultimate Health Care Cost Trend Rate	4.50%	4.50%
DefinedBenefitPlanWeightedAverageAssumptionsUsedInCalculatingNetPeriodicBenefitCostAbstract
Discount Rate	3.15%	4.20%
Defined Benefit Plan Assumed Health Care Cost Trend Rates Net Periodic [Abstract]
Rate Assumed for Next Fiscal Year	7.50%	7.85%
Ultimate Health Care Cost Trend Rate	4.50%	4.50%