Stock Compensation Plans: Disclosure of Share-based Compensation Arrangements by Share-based Payment Award (Details) - $ / shares	9 Months Ended
	Jun. 30, 2023	Jun. 30, 2022
Shares:
Options outstanding, beginning of period (shares)	421,925	406,815
Exercised (shares)	(27,055)	(29,770)
Granted (shares)	1,000	1,000
Forfeited (shares)	(7,800)	(18,170)
Options outstanding, end of period (shares)	388,070	359,875
Weighted Average Exercise Price (in dollars per share):
Options outstanding, beginning of period (dollars per share)	$ 23.30	$ 21.62
Exercised (dollars per share)	19.77	12.05
Granted (dollars per share)	33.40	27.25
Forfeited (dollars per share)	28.23	25.98
Options outstanding, end of period (dollars per share)	$ 23.47	$ 22.20