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EMPLOYEE BENEFIT PLANS Table 9 - Assumptions - Health Care Cost Trend Rates (Details)
12 Months Ended
Dec. 31, 2020
Dec. 31, 2019
Defined Benefit Plan Disclosure [Line Items]    
Health care cost trend rate assumed for next year 6.84% 6.84%
Rate to which the cost trend rate was assumed to decrease (the ultimate trend rate) 5.00% 5.00%
Year that the rate reaches the ultimate trend rate 2028 2028
Other Postretirement Benefit Plans [Member]    
Defined Benefit Plan Disclosure [Line Items]    
Cap on increase in the employer's cost The cap on the increase in employer’s cost is 2.5% per year.