Loans Receivable And Allowance For Loan Losses: Schedule of Allowance for Loan Losses (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended	9 Months Ended
Jun. 30, 2026	Jun. 30, 2025	Mar. 31, 2026	Jun. 30, 2026	Jun. 30, 2025
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, Beginning Allowance	$ 18,648	$ 17,525	$ 18,091	$ 18,091	$ 17,478
Provision for (Recapture of) Credit Losses	600	351		1,140	640
Charge- Offs	0	0		0	(245)
Recoveries	1	2		18	5
Allowance for loan losses, Ending Allowance	19,249	17,878	18,648	19,249	17,878
One-to four-family
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, Beginning Allowance	2,821	2,800	2,892	2,892	2,632
Provision for (Recapture of) Credit Losses	(285)	93		(356)	261
Charge- Offs	0	0		0	0
Recoveries	0	0		0	0
Allowance for loan losses, Ending Allowance	2,536	2,893	2,821	2,536	2,893
Multi-family
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, Beginning Allowance	1,639	1,315	1,625	1,625	1,308
Provision for (Recapture of) Credit Losses	(86)	265		(72)	272
Charge- Offs	0	0		0	0
Recoveries	0	0		0	0
Allowance for loan losses, Ending Allowance	1,553	1,580	1,639	1,553	1,580
Commercial real estate
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, Beginning Allowance	7,479	6,983	7,147	7,147	6,934
Provision for (Recapture of) Credit Losses	409	180		741	229
Charge- Offs	0	0		0	0
Recoveries	0	0		0	0
Allowance for loan losses, Ending Allowance	7,888	7,163	7,479	7,888	7,163
Construction-custom & owner/builder (1)
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, Beginning Allowance	1,175	1,217	1,268	1,268	1,328
Provision for (Recapture of) Credit Losses	324	25		231	(86)
Charge- Offs	0	0		0	0
Recoveries	0	0		0	0
Allowance for loan losses, Ending Allowance	1,499	1,242	1,175	1,499	1,242
Construction-speculative one-to four-family (1)
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, Beginning Allowance	181	89	112	112	128
Provision for (Recapture of) Credit Losses	111	8		180	(31)
Charge- Offs	0	0		0	0
Recoveries	0	0		0	0
Allowance for loan losses, Ending Allowance	292	97	181	292	97
Construction-commercial (1)
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, Beginning Allowance	257	358	348	348	537
Provision for (Recapture of) Credit Losses	81	(101)		(10)	(280)
Charge- Offs	0	0		0	0
Recoveries	0	0		0	0
Allowance for loan losses, Ending Allowance	338	257	257	338	257
Construction-multi-family (1)
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, Beginning Allowance	969	543	400	400	456
Provision for (Recapture of) Credit Losses	484	(165)		1,053	(78)
Charge- Offs	0	0		0	0
Recoveries	0	0		0	0
Allowance for loan losses, Ending Allowance	1,453	378	969	1,453	378
Construction-land development (1)
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, Beginning Allowance	80	375	412	412	335
Provision for (Recapture of) Credit Losses	(68)	38		(400)	78
Charge- Offs	0	0		0
Recoveries	0	0		0	0
Allowance for loan losses, Ending Allowance	12	413	80	12	413
Land
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, Beginning Allowance	684	852	797	797	793
Provision for (Recapture of) Credit Losses	(112)	(39)		(225)	20
Charge- Offs	0	0		0	0
Recoveries	0	0		0	0
Allowance for loan losses, Ending Allowance	572	813	684	572	813
Home equity and second mortgage
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, Beginning Allowance	452	345	435	435	348
Provision for (Recapture of) Credit Losses	(88)	66		(71)	63
Charge- Offs	0	0		0	0
Recoveries	0	0		0	0
Allowance for loan losses, Ending Allowance	364	411	452	364	411
Consumer loans, other
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, Beginning Allowance	51	33	58	58	39
Provision for (Recapture of) Credit Losses	1	4		(6)	2
Charge- Offs	0	0		0	(4)
Recoveries	1	1		1	1
Allowance for loan losses, Ending Allowance	53	38	51	53	38
Commercial business
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for loan losses, Beginning Allowance	2,860	2,615	2,597	2,597	2,640
Provision for (Recapture of) Credit Losses	(171)	(23)		75	190
Charge- Offs	0	0		0	(241)
Recoveries	0	1		17	4
Allowance for loan losses, Ending Allowance	$ 2,689	$ 2,593	$ 2,860	$ 2,689	$ 2,593

Amount excluding accrued interest, of allowance for credit loss on financing receivable. Excludes net investment in lease.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479344/326-20-45-1

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Amount, excluding accrued interest, of increase in allowance for credit loss on financing receivable from recovery. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (e)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-13

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Amount, excluding accrued interest, of decrease in allowance for credit loss on financing receivable from writeoff. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-13

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-6

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Amount, excluding accrued interest, of credit loss expense (reversal of expense) on financing receivable. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-13

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 220
-SubTopic 40
-Name Accounting Standards Codification
-Section 50
-Paragraph 22
-Subparagraph (a)
-Publisher FASB
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