Derivative Financial Instruments (Narrative) (Details) - USD ($)	Mar. 31, 2022	Sep. 30, 2021
Derivative Instruments And Hedging Activities Disclosure [Abstract]
Cash collateral held		$ 0
Cash collateral posted	$ 0

Amount of obligation to return cash collateral under master netting arrangements that have not been offset against derivative assets.

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-Publisher FASB
-Name Accounting Standards Codification
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Name:	us-gaap_DerivativeCollateralObligationToReturnCash
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant