Investment Securities: Marketable Securities (Details) - USD ($)	Sep. 30, 2024	Sep. 30, 2023
Held to Maturity
Amortized Cost	$ 172,097,000	$ 270,218,000
Gross Unrealized Gains	483,000	295,000
Gross Unrealized Losses	(6,573,000)	(16,747,000)
Estimated Fair Value	166,007,000	253,766,000
ACL	60,000	0
Available for Sale
Total	72,231,000	43,132,000
Gross Unrealized Gains	551,000	0
Gross Unrealized Losses	525,000	1,361,000
Estimated Fair Value	72,257,000	41,771,000
U.S. agency securities
Held to Maturity
Amortized Cost	92,312,000	171,626,000
Gross Unrealized Gains	70,000	0
Gross Unrealized Losses	(4,197,000)	(10,088,000)
Estimated Fair Value	88,185,000	161,538,000
ACL	0
Available for Sale
Total	3,934,000
Gross Unrealized Gains	6,000
Gross Unrealized Losses	1,000
Estimated Fair Value	3,939,000
U.S. government agencies
Held to Maturity
Amortized Cost	49,481,000	52,294,000
Gross Unrealized Gains	174,000	0
Gross Unrealized Losses	(1,378,000)	(3,950,000)
Estimated Fair Value	48,277,000	48,344,000
ACL	0
Available for Sale
Total	68,297,000	43,132,000
Gross Unrealized Gains	545,000	0
Gross Unrealized Losses	524,000	1,361,000
Estimated Fair Value	68,318,000	41,771,000
Private label residential
Held to Maturity
Amortized Cost	28,479,000	44,011,000
Gross Unrealized Gains	231,000	295,000
Gross Unrealized Losses	(980,000)	(2,611,000)
Estimated Fair Value	27,730,000	41,695,000
ACL	55,000	0
Municipal securities
Held to Maturity
Amortized Cost	1,330,000	1,787,000
Gross Unrealized Gains	8,000	0
Gross Unrealized Losses	0	(47,000)
Estimated Fair Value	1,338,000	1,740,000
ACL	0
Bank issued trust preferred securities
Held to Maturity
Amortized Cost	495,000	500,000
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(18,000)	(51,000)
Estimated Fair Value	477,000	449,000
ACL	$ 5,000	$ 0