Loans - Schedule of Activity in Allowance for Loan Losses, Excluding Accrued Interest (Details) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2025 USD ($) loan	Jun. 30, 2024 USD ($)	Jun. 30, 2025 USD ($) loan	Jun. 30, 2024 USD ($) loan
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Beginning Allowance	$ 8,393	$ 8,598	$ 8,499	$ 8,760
Charge-offs	(23)	(21)	(50)	(83)
Recoveries	2	4	8	10
Provision for (Release of) Credit Losses	164	(88)	79	(194)
Ending Allowance	8,536	8,493	8,536	8,493
Real estate loans: \| One-to-four family:
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Beginning Allowance	3,328	2,910	3,025	2,630
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Provision for (Release of) Credit Losses	(1)	(112)	302	168
Ending Allowance	3,327	2,798	3,327	2,798
Real estate loans: \| Home equity:
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Beginning Allowance	362	179	307	185
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Provision for (Release of) Credit Losses	(2)	20	53	14
Ending Allowance	360	199	360	199
Real estate loans: \| Commercial and multifamily:
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Beginning Allowance	1,181	1,106	1,218	1,070
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Provision for (Release of) Credit Losses	55	24	18	60
Ending Allowance	1,236	1,130	1,236	1,130
Real estate loans: \| Construction and land:
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Beginning Allowance	279	1,329	992	1,349
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Provision for (Release of) Credit Losses	(10)	(257)	(723)	(277)
Ending Allowance	269	1,072	269	1,072
Consumer loans: \| Manufactured homes:
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Beginning Allowance	1,303	833	1,172	971
Charge-offs	0		(19)	(23)
Recoveries	0	0	0	0
Provision for (Release of) Credit Losses	92	105	242	(10)
Ending Allowance	1,395	938	$ 1,395	$ 938
Number of loans charged off \| loan			1	1
Consumer loans: \| Floating homes:
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Beginning Allowance	1,409	1,799	$ 1,282	$ 2,022
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Provision for (Release of) Credit Losses	1	111	128	(112)
Ending Allowance	1,410	1,910	1,410	1,910
Consumer loans: \| Other consumer
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Beginning Allowance	448	333	401	426
Charge-offs	(23)	(21)	(31)	(60)
Recoveries	2	4	8	10
Provision for (Release of) Credit Losses	24	32	73	(28)
Ending Allowance	451	348	451	348
Consumer loans: \| Other consumer \| Consumer Borrower
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Charge-offs	$ (16)		$ (23)
Number of loans charged off \| loan	1		1
Commercial business
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Beginning Allowance	$ 83	109	$ 102	107
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Provision for (Release of) Credit Losses	5	(11)	(14)	(9)
Ending Allowance	$ 88	98	$ 88	98
Unallocated
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Beginning Allowance				0
Charge-offs				0
Recoveries				0
Provision for (Release of) Credit Losses				0
Ending Allowance		$ 0		$ 0

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- Definition

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

+ References

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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- Definition

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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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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- Definition

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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- Definition

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
-URI https://asc.fasb.org/1943274/2147476148/220-40-50-22

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