Retirement Plan And Other Post-Retirement Benefits (Narrative) (Details) $ in Millions	9 Months Ended
Jun. 30, 2023 USD ($)
Retirement Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Company's contributions	$ 0.0
VEBA Trusts [Member]
Defined Benefit Plan Disclosure [Line Items]
Company's contributions	$ 0.0

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

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration