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Benefit Plans Contributions (Details) $ in Millions	3 Months Ended
	Dec. 31, 2019 USD ($)
Retirement Plan Disclosure
Remaining Employer Contributions	$ 225
Contributions to 401K	24
Other Pension Plan
Retirement Plan Disclosure
Defined benefit plan contributions	75
defined benefit plan, plan assets, monthly contributions by employer	25
Other Post-retirement Benefits
Retirement Plan Disclosure
Defined benefit plan contributions	10
SERP
Retirement Plan Disclosure
Defined benefit plan contributions	5
Minimum | Other Pension Plan
Retirement Plan Disclosure
Defined benefit plan contributions	$ 300

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-Publisher FASB
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