Loans Receivable and Allowance for Credit Losses - Troubled Debt Restructuring (Details) $ in Thousands	12 Months Ended
Dec. 31, 2022 USD ($) loan	Dec. 31, 2021 USD ($) loan	Dec. 31, 2020 USD ($) loan
Financing Receivable, Troubled Debt Restructuring [Line Items]
No. of Loans \| loan	1	3	7
Pre-modification Recorded Investment	$ 119	$ 477	$ 28,529
Post-modification Recorded Investment	$ 119	$ 599	$ 29,824
Real estate loans \| One-to-four family
Financing Receivable, Troubled Debt Restructuring [Line Items]
No. of Loans \| loan	0	2
Pre-modification Recorded Investment	$ 0	$ 285
Post-modification Recorded Investment	$ 0	$ 388
Real estate loans \| Commercial real estate
Financing Receivable, Troubled Debt Restructuring [Line Items]
No. of Loans \| loan	0	1	5
Pre-modification Recorded Investment	$ 0	$ 192	$ 17,022
Post-modification Recorded Investment	$ 0	$ 211	$ 17,022
Consumer loans \| Home equity loans and advances
Financing Receivable, Troubled Debt Restructuring [Line Items]
No. of Loans \| loan	1	0
Pre-modification Recorded Investment	$ 119	$ 0
Post-modification Recorded Investment	$ 119	$ 0
Commercial business loans
Financing Receivable, Troubled Debt Restructuring [Line Items]
No. of Loans \| loan			2
Pre-modification Recorded Investment			$ 11,507
Post-modification Recorded Investment			$ 12,802

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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 https://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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