XML 116 R114.htm IDEA: XBRL DOCUMENT v3.19.3
Benefit Plans Sensitivity to Changes in Assumed Health Care Cost Trend Rates (Details)
$ in Millions
12 Months Ended
Sep. 30, 2019
USD ($)
Maximum  
Defined Benefit Plan Disclosure  
Effect of one percentage point increase on total service and interest cost components $ 4
Effect of one percentage point increase on end-of-year accumulated postretirement benefit obligation 71
Minimum  
Defined Benefit Plan Disclosure  
Effect of one percentage point decrease on total service and interest cost components (4)
Effect of one percentage point decrease on end-of-year accumulated postretirement benefit obligation $ (68)