Loans Receivable and Allowance for Credit Losses - Interest Income on Impaired Loans (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2022	Mar. 31, 2021
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	$ 24,627	$ 44,175
Interest Income Recognized	341	550
Real estate loans \| One-to-four family
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	5,030	6,944
Interest Income Recognized	55	74
Real estate loans \| Multifamily
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	752	16,060
Interest Income Recognized	11	173
Real estate loans \| Commercial real estate
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	16,423	16,603
Interest Income Recognized	242	252
Commercial business loans
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	1,626	2,957
Interest Income Recognized	22	29
Consumer loans \| Home equity loans and advances
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	796	1,611
Interest Income Recognized	$ 11	$ 22

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 http://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 http://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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