Loans Receivable and Allowance for Loan Losses - Troubled Debt Restructuring (Details) $ in Thousands	12 Months Ended
Dec. 31, 2021 USD ($) loan	Dec. 31, 2020 USD ($) loan	Dec. 31, 2019 USD ($) loan
Financing Receivable, Troubled Debt Restructuring [Line Items]
No. of Loans \| loan	3	7	1
Pre-modification Recorded Investment	$ 477	$ 28,529	$ 4,095
Post-modification Recorded Investment	$ 599	$ 29,824	$ 4,095
Real estate loans \| One-to-four family
Financing Receivable, Troubled Debt Restructuring [Line Items]
No. of Loans \| loan	2	0
Pre-modification Recorded Investment	$ 285	$ 0
Post-modification Recorded Investment	$ 388	$ 0
Real estate loans \| Multifamily and commercial
Financing Receivable, Troubled Debt Restructuring [Line Items]
No. of Loans \| loan	1	5
Pre-modification Recorded Investment	$ 192	$ 17,022
Post-modification Recorded Investment	$ 211	$ 17,022
Commercial business loans
Financing Receivable, Troubled Debt Restructuring [Line Items]
No. of Loans \| loan	0	2	1
Pre-modification Recorded Investment	$ 0	$ 11,507	$ 4,095
Post-modification Recorded Investment	$ 0	$ 12,802	$ 4,095

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No definition available.

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Number of financing receivables that have been modified by troubled debt restructurings.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=123577603&loc=SL6953676-111524

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Amount, after troubled debt restructuring, of modified financing receivable.

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- Definition

Amount, before troubled debt restructuring, of financing receivable to be modified.

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