XML 57 R93.htm IDEA: XBRL DOCUMENT v3.19.3.a.u2
Employee Benefit Plans and Other Postretirement Benefits - Schedule of Assumed Health Care Cost Trend Rates for Postretirement Benefits (Details) - Postretirement Plans
12 Months Ended
Dec. 31, 2019
Dec. 31, 2018
Dec. 31, 2017
Defined Benefit Plans and Other Postretirement Benefit Plans [Line Items]      
Health care cost trend rate assumed for next year 7.09% 7.24% 7.57%
Rate to which the cost trend rate is assumed to decline (the ultimate trend rate) 4.50% 4.44% 4.44%
Year that the rate reaches the ultimate trend rate 2029 2028 2027