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Benefit Plans Sensitivity to Changes in Assumed Health Care Cost Trend Rates (Details) $ in Millions | 12 Months Ended
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Sep. 30, 2020 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 | 70
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)

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- Definition Amount of decrease in accumulated postretirement benefit obligation from one-percentage-point decrease in assumed health care cost trend rate. + References Reference 1: http://fasb.org/us-gaap/role/ref/otherTransitionRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (m) -URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920 + Details
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