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Benefit Plans Contributions (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
	Jun. 30, 2021	Jun. 30, 2021
Retirement Plan Disclosure
Remaining Employer Contributions		$ 75
Other Pension Plan
Retirement Plan Disclosure
Defined benefit plan contributions		225
defined benefit plan, plan assets, monthly contributions by employer		25
Other Post-retirement Benefits
Retirement Plan Disclosure
Defined benefit plan contributions		20
SERP
Retirement Plan Disclosure
Defined benefit plan contributions	$ 6
Rebates [Member]
Retirement Plan Disclosure
Defined benefit plan contributions		2
401K [Member]
Retirement Plan Disclosure
Defined benefit plan contributions		$ 70
Minimum | Other Pension Plan
Retirement Plan Disclosure
Defined benefit plan contributions	$ 300

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