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Benefit Plans Contributions (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended	12 Months Ended
	Mar. 31, 2019	Mar. 31, 2019	Sep. 30, 2019
Other Pension Plan
Retirement Plan Disclosure
Defined benefit plan contributions		$ 150	$ 25
Other Post-retirement Benefits
Retirement Plan Disclosure
Defined benefit plan contributions		150
SERP
Retirement Plan Disclosure
Defined benefit plan contributions	$ 5	1
Minimum | Other Pension Plan
Retirement Plan Disclosure
Defined benefit plan contributions	44	$ 300
Minimum | Other Post-retirement Benefits
Retirement Plan Disclosure
Defined benefit plan contributions	$ 20

X

- Definition

Amount of contribution received by defined benefit plan from employer which increases plan assets.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 55
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-Section 50
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- Definition

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+ References

No definition available.

+ Details

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