Loans Receivable And Allowance For Loan Losses: Impaired Financing Receivables (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended	12 Months Ended
	Jun. 30, 2023		Jun. 30, 2023	Sep. 30, 2022
Recorded Investment
With no related allowance recorded	$ 3,945		$ 3,945	$ 4,282
With an allowance recorded	245		245	250
Total:	4,190		4,190	4,532
Unpaid Principal Balance (Loan Balance Plus Charge Off)
With no related allowance recorded	4,037		4,037	4,375
With an allowance recorded	245		245	250
Total:	4,282		4,282	4,625
Related Allowance	123		123	127
Average Recorded Investment
With no related allowance recorded	4,110	[1]	4,188	4,567
With an allowance recorded	247	[1]	247	413
Total	4,357	[1]	4,435	4,980
Interest Income Recognized
With no related allowance recorded	52	[1]	155	189	[1]
With an allowance recorded	0	[1]	0	0
Total	52	[1]	155	189
Cash Basis Interest Income Recognized
With no related allowance recorded	41	[1]	125	159
With an allowance recorded	0	[1]	0	0
Total	41	[1]	125	159
Mortgage loans, one-to-four family
Recorded Investment
With no related allowance recorded	373		373	388
Total:	373		373	388
Unpaid Principal Balance (Loan Balance Plus Charge Off)
With no related allowance recorded	417		417	432
Total:	417		417	432
Related Allowance	0		0	0
Average Recorded Investment
With no related allowance recorded	376	[1]	381	470
Total	376	[1]	381	470
Interest Income Recognized
With no related allowance recorded	7	[1]	21	31	[1]
Total	7	[1]	21	31
Cash Basis Interest Income Recognized
With no related allowance recorded	7	[1]	21	31
Total	7	[1]	21	31
Mortgage loans, commercial
Recorded Investment
With no related allowance recorded	2,988		2,988	2,988
Total:	2,988		2,988	2,988
Unpaid Principal Balance (Loan Balance Plus Charge Off)
With no related allowance recorded	2,988		2,988	2,988
Total:	2,988		2,988	2,988
Related Allowance	0		0	0
Average Recorded Investment
With no related allowance recorded	2,894	[1]	2,939	3,041
Total	2,894	[1]	2,939	3,041
Interest Income Recognized
With no related allowance recorded	40	[1]	121	152	[1]
Total	40	[1]	121	152
Cash Basis Interest Income Recognized
With no related allowance recorded	31	[1]	94	123
Total	31	[1]	94	123
Mortgage loans, land
Recorded Investment
With no related allowance recorded	150		150	450
Total:	150		150	450
Unpaid Principal Balance (Loan Balance Plus Charge Off)
With no related allowance recorded	150		150	450
Total:	150		150	450
Related Allowance	0		0	0
Average Recorded Investment
With no related allowance recorded	305	[1]	371	492
Total	305	[1]	371	492
Interest Income Recognized
With no related allowance recorded	2	[1]	4	0	[1]
Total	2	[1]	4	0
Cash Basis Interest Income Recognized
With no related allowance recorded	1	[1]	3	0
Total	1	[1]	3	0
Consumer loans, home equity and second mortgage
Recorded Investment
With no related allowance recorded	390		390	394
With an allowance recorded				0
Total:	390		390	394
Unpaid Principal Balance (Loan Balance Plus Charge Off)
With no related allowance recorded	390		390	394
With an allowance recorded				0
Total:	390		390	394
Related Allowance	0		0	0
Average Recorded Investment
With no related allowance recorded	488	[1]	444	436
With an allowance recorded				145
Total	488	[1]	444	581
Interest Income Recognized
With no related allowance recorded	3	[1]	9	6	[1]
With an allowance recorded				0
Total	3	[1]	9	6
Cash Basis Interest Income Recognized
With no related allowance recorded	2	[1]	7	5
With an allowance recorded				0
Total	2	[1]	7	5
Consumer loans, other
Recorded Investment
With no related allowance recorded	0		0	3
Total:	0		0	3
Unpaid Principal Balance (Loan Balance Plus Charge Off)
With no related allowance recorded	48		48	3
Total:	48		48	3
Related Allowance	0		0	0
Average Recorded Investment
With no related allowance recorded	1	[1]	2	7
Total	1	[1]	2	7
Interest Income Recognized
With no related allowance recorded	0	[1]	0	0
Total	0	[1]	0	0
Cash Basis Interest Income Recognized
With no related allowance recorded	0	[1]	0
With an allowance recorded				0
Total	0	[1]	0	0
Commercial business loans
Recorded Investment
With no related allowance recorded	44		44	59
With an allowance recorded	245		245	250
Total:	289		289	309
Unpaid Principal Balance (Loan Balance Plus Charge Off)
With no related allowance recorded	44		44	108
With an allowance recorded	245		245	250
Total:	289		289	358
Related Allowance	123		123	127
Average Recorded Investment
With no related allowance recorded	46	[1]	51	121
With an allowance recorded	247		247	268
Total	293	[1]	298	389
Interest Income Recognized
With no related allowance recorded	0	[1]	0	0	[1]
With an allowance recorded	0	[1]	0	0
Total	0	[1]	0	0
Cash Basis Interest Income Recognized
With no related allowance recorded	0	[1]	0	0
With an allowance recorded	0	[1]	0	0
Total	$ 0	[1]	$ 0	$ 0

[1] For the three months ended June 30, 2023