Loans Receivable and Allowance for Credit Losses - Amortized cost basis of loans on nonaccrual status (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Financing Receivable, Nonaccrual [Line Items]
Nonaccrual Loans with a related ACL	$ 1,714	$ 1,211
Nonaccrual loans without a related ACL	491	1,049
Total Nonaccrual Loans	2,205	2,260
Total Nonaccrual Loans	2,205	2,260
One- to four-family residential
Financing Receivable, Nonaccrual [Line Items]
Nonaccrual Loans with a related ACL	1,535	1,030
Nonaccrual loans without a related ACL	491	1,049
Total Nonaccrual Loans	2,026	2,079
Total Nonaccrual Loans	2,026	2,079
Home equity loans and lines of credit
Financing Receivable, Nonaccrual [Line Items]
Nonaccrual Loans with a related ACL	9	11
Total Nonaccrual Loans	9	11
Total Nonaccrual Loans	9	11
Consumer and other
Financing Receivable, Nonaccrual [Line Items]
Nonaccrual Loans with a related ACL	170	170
Total Nonaccrual Loans	170	170
Total Nonaccrual Loans	$ 170	$ 170

Amortized cost of financing receivable on nonaccrual status.

No definition available.

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- Definition

Amortized cost of financing receivable on nonaccrual status with allowance for credit loss.

+ References

No definition available.

+ Details

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- Definition

Amortized cost of financing receivable on nonaccrual status with no allowance for credit loss. 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 16
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479319/326-20-50-16

+ Details

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 16
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479319/326-20-50-16

+ Details

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- Definition

Amortized cost of financing receivable on nonaccrual status. 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 16
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479319/326-20-50-16

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Name Regulation S-K (SK)
-Number 229
-Section 1405
-Paragraph (a)
-Subparagraph (3)
-Publisher SEC

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Name Regulation S-K (SK)
-Number 229
-Section 1405
-Paragraph (a)
-Subparagraph (2)
-Publisher SEC

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 7
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481962/310-10-50-7

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