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Pension and Retirement Plans - Schedule of Assumed Health Care Cost Trend Rates (Details) - Postretirement Healthcare Plan
12 Months Ended
Dec. 31, 2019
Dec. 31, 2018
Defined Benefit Plan Disclosure [Line Items]    
Health care cost trend rate assumed for next year 4.00% 4.00%
Rate to which the cost trend rate is assumed to decline (the ultimate trend rate) 4.00% 4.00%
Year that the rate reaches the ultimate trend rate 2019 2018