OREO and Other Repossessed Assets: Narrative (Details)	12 Months Ended
	Sep. 30, 2022 USD ($) property loan	Sep. 30, 2021 USD ($) loan property	Sep. 30, 2020 USD ($)
Other Real Estate, Foreclosed Assets, and Repossessed Assets [Abstract]
(Gain) loss on sales of OREO and other repossessed assets, net	$ 2,000	$ 92,000	$ 35,000
OREO, number of repossessed assets | loan	0	0
Number of other repossessed assets | property	0	1
Recorded amount of foreclosed residential real estate properties held in OREO		$ 30,000