Loans Receivable and Allowance for Credit Losses - Interest Income on Impaired Loans (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	$ 29,676	$ 22,981	$ 26,712	$ 23,803
Interest Income Recognized	366	245	865	837
Real estate loans \| One-to-four family
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	4,329	4,251	4,394	4,640
Interest Income Recognized	54	45	154	146
Real estate loans \| Multifamily
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	411	598	429	675
Interest Income Recognized	5	6	15	28
Real estate loans \| Commercial real estate
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	16,653	16,086	16,452	16,254
Interest Income Recognized	214	163	516	568
Commercial business loans
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	7,657	1,269	4,780	1,447
Interest Income Recognized	78	22	148	66
Consumer loans \| Home equity loans and advances
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	626	777	657	787
Interest Income Recognized	$ 15	$ 9	$ 32	$ 29

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Average amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (c)(1)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481962/310-10-50-15

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 17
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481962/310-10-50-17

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Amount of interest income recognized that the financing receivables (with related allowance for credit losses and without a related allowance for credit losses) were impaired.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (c)(2)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481962/310-10-50-15

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