Loans Receivable and Allowance for Credit Losses - Schedule of Allowance for Loan and Lease Losses, Roll Forward (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance			$ 15,227
Provision (recapture)	$ (247)		91
Ending balance	15,606		15,606
One-to-Four Family Residential
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	5,611	$ 3,475	4,043	$ 3,214
Charge-offs	0	0	0	0
Recoveries	0	(3)	(1)	(5)
Provision (recapture)	(37)	214	10	473
Ending balance	5,574	3,692	5,574	3,692
Total Loans		436,754		436,754
Loans collectively evaluated for impairment		434,672		434,672
Loans individually evaluated for impairment		2,082		2,082
One-to-Four Family Residential \| General Allowance
Allowance for Loan and Lease Losses [Roll Forward]
Ending balance		3,676		3,676
One-to-Four Family Residential \| Specific Allowance
Allowance for Loan and Lease Losses [Roll Forward]
Ending balance		16		16
One-to-Four Family Residential \| Cumulative Effect, Period of Adoption, Adjustment
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance			1,520
Multifamily
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	1,607	1,455	1,210	1,279
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Provision (recapture)	(25)	(159)	289	17
Ending balance	1,582	1,296	1,582	1,296
Total Loans		135,961		135,961
Loans collectively evaluated for impairment		134,310		134,310
Loans individually evaluated for impairment		1,651		1,651
Multifamily \| General Allowance
Allowance for Loan and Lease Losses [Roll Forward]
Ending balance		1,296		1,296
Multifamily \| Specific Allowance
Allowance for Loan and Lease Losses [Roll Forward]
Ending balance		0		0
Multifamily \| Cumulative Effect, Period of Adoption, Adjustment
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance			83
Commercial real estate
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	4,496	6,315	5,397	6,615
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Provision (recapture)	(129)	(128)	(60)	(428)
Ending balance	4,367	6,187	4,367	6,187
Total Loans		412,693		412,693
Loans collectively evaluated for impairment		372,743		372,743
Loans individually evaluated for impairment		39,950		39,950
Commercial real estate \| General Allowance
Allowance for Loan and Lease Losses [Roll Forward]
Ending balance		6,187		6,187
Commercial real estate \| Specific Allowance
Allowance for Loan and Lease Losses [Roll Forward]
Ending balance		0		0
Commercial real estate \| Cumulative Effect, Period of Adoption, Adjustment
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance			(970)
Construction Land Development
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	1,793	1,642	1,717	2,064
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Provision (recapture)	(129)	(285)	(461)	(707)
Ending balance	1,664	1,357	1,664	1,357
Total Loans		64,347		64,347
Loans collectively evaluated for impairment		64,347		64,347
Loans individually evaluated for impairment		0		0
Construction Land Development \| General Allowance
Allowance for Loan and Lease Losses [Roll Forward]
Ending balance		1,357		1,357
Construction Land Development \| Specific Allowance
Allowance for Loan and Lease Losses [Roll Forward]
Ending balance		0		0
Construction Land Development \| Cumulative Effect, Period of Adoption, Adjustment
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance			408
Business
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	413	781	948	1,112
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Provision (recapture)	(66)	217	(91)	(114)
Ending balance	347	998	347	998
Total Loans		33,692		33,692
Loans collectively evaluated for impairment		33,692		33,692
Loans individually evaluated for impairment		0		0
Business \| General Allowance
Allowance for Loan and Lease Losses [Roll Forward]
Ending balance		998		998
Business \| Specific Allowance
Allowance for Loan and Lease Losses [Roll Forward]
Ending balance		0		0
Business \| Cumulative Effect, Period of Adoption, Adjustment
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance			(510)
Prior
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	2,108	1,491	1,912	1,373
Charge-offs	(22)	(37)	(22)	(37)
Recoveries	0	0	0	0
Provision (recapture)	(14)	141	213	259
Ending balance	2,072	1,595	2,072	1,595
Total Loans		51,603		51,603
Loans collectively evaluated for impairment		51,603		51,603
Loans individually evaluated for impairment		0		0
Prior \| General Allowance
Allowance for Loan and Lease Losses [Roll Forward]
Ending balance		1,595		1,595
Prior \| Specific Allowance
Allowance for Loan and Lease Losses [Roll Forward]
Ending balance		0		0
Prior \| Cumulative Effect, Period of Adoption, Adjustment
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance			(31)
Property total
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	16,028	15,159	15,227	15,657
Charge-offs	(22)	(37)	(22)	(37)
Recoveries	0	(3)	(1)	(5)
Provision (recapture)	(400)	0	(100)	(500)
Ending balance	$ 15,606	15,125	15,606	15,125
Total Loans		1,135,050		1,135,050
Loans collectively evaluated for impairment		1,091,367		1,091,367
Loans individually evaluated for impairment		43,683		43,683
Property total \| General Allowance
Allowance for Loan and Lease Losses [Roll Forward]
Ending balance		15,109		15,109
Property total \| Specific Allowance
Allowance for Loan and Lease Losses [Roll Forward]
Ending balance		$ 16		$ 16
Property total \| Cumulative Effect, Period of Adoption, Adjustment
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance			$ 500

Financing Receivable, Excluding Accrued Interest, Expense Provision (Reversal)

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

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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

The balance of financing receivables that were collectively evaluated for impairment.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 4
-Subparagraph (SAB Topic 6.L(5)(a))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480418/310-10-S99-4

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 11C
-Subparagraph (a)
-Publisher FASB
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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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- 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

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- Definition

The balance of financing receivables that were individually evaluated for impairment.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 11C
-Subparagraph (b)
-Publisher FASB
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