Receivable and Allowance for Credit Losses - Interest Income on Impaired Loans (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Recorded Investment
Average Recorded Investment	$ 27,762	$ 23,536	$ 34,311
Interest Income Recognized	1,282	1,091	1,305
Real estate loans \| One-to-four family
Recorded Investment
Average Recorded Investment	4,328	4,385	5,738
Interest Income Recognized	196	203	285
Real estate loans \| Multifamily
Recorded Investment
Average Recorded Investment	420	598	8,420
Interest Income Recognized	19	28	371
Real estate loans \| Commercial real estate
Recorded Investment
Average Recorded Investment	16,234	16,479	16,913
Interest Income Recognized	694	733	467
Commercial business loans
Recorded Investment
Average Recorded Investment	6,134	1,289	2,121
Interest Income Recognized	331	88	139
Consumer loans \| Home equity loans and advances
Recorded Investment
Average Recorded Investment	646	785	1,119
Interest Income Recognized	$ 42	$ 39	$ 43

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No definition available.

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- Definition

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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- Definition

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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