Loans Receivable and Allowance for Credit Losses - Interest Income on Impaired Loans (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2024	Mar. 31, 2023
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	$ 26,327	$ 23,751
Interest Income Recognized	35	257
Real estate loans \| One-to-four family
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	2,896	4,459
Interest Income Recognized	13	45
Real estate loans \| Multifamily
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	214	448
Interest Income Recognized	1	5
Real estate loans \| Commercial real estate
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	12,528	16,252
Interest Income Recognized	20	151
Commercial business loans
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	10,333	1,904
Interest Income Recognized	0	49
Consumer loans \| Home equity loans and advances
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	356	688
Interest Income Recognized	$ 1	$ 7

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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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