Loans Receivable and Allowance for Credit Losses - Interest Income on Impaired Loans (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2023	Mar. 31, 2022
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	$ 23,751	$ 24,627
Interest Income Recognized	257	341
Real estate loans \| One-to-four family
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	4,459	5,030
Interest Income Recognized	45	55
Real estate loans \| Multifamily
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	448	752
Interest Income Recognized	5	11
Real estate loans \| Commercial real estate
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	16,252	16,423
Interest Income Recognized	151	242
Commercial business loans
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	1,904	1,626
Interest Income Recognized	49	22
Consumer loans \| Home equity loans and advances
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	688	796
Interest Income Recognized	$ 7	$ 11

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.

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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (c)(1)
-URI https://asc.fasb.org/extlink&oid=123577603&loc=d3e5212-111524

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 17
-URI https://asc.fasb.org/extlink&oid=123577603&loc=d3e5258-111524

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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

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