OREO and Other Repossessed Assets: Narrative (Details) $ in Thousands	12 Months Ended
Sep. 30, 2023 USD ($) property loan	Sep. 30, 2022 USD ($)	Sep. 30, 2021 USD ($)
Other Real Estate, Foreclosed Assets, and Repossessed Assets [Abstract]
(Gain) loss on sales of OREO and other repossessed assets, net \| $	$ 0	$ 2	$ 92
OREO, number of repossessed assets \| loan	0
Number of other repossessed assets \| property	0

The net gain (loss) resulting from sales and other disposals of other real estate owned, increases (decreases) in the valuation allowance for foreclosed real estate, and write-downs of other real estate owned after acquisition or physical possession.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 942
-SubTopic 220
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04.14(d))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483589/942-220-S99-1

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Period Type:	duration