Loans Receivable and Allowance for Loan Losses - Interest Income on Impaired Loans (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Recorded Investment
Average Recorded Investment	$ 34,311	$ 38,519	$ 21,240
Interest Income Recognized	1,305	1,712	1,203
Real estate loans \| One-to-four family
Recorded Investment
Average Recorded Investment	5,738	7,946	8,811
Interest Income Recognized	285	305	434
Real estate loans \| Multifamily and commercial
Recorded Investment
Average Recorded Investment	25,333	23,701	2,639
Interest Income Recognized	838	1,091	147
Real estate loans \| Construction
Recorded Investment
Average Recorded Investment	0	0	850
Interest Income Recognized	0	0	0
Commercial business loans
Recorded Investment
Average Recorded Investment	2,121	4,963	6,378
Interest Income Recognized	139	216	479
Consumer loans \| Home equity loans and advances
Recorded Investment
Average Recorded Investment	1,119	1,909	2,562
Interest Income Recognized	$ 43	$ 100	$ 143

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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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