Loans Receivable - Troubled Debt Restructurings (Details) $ in Thousands	3 Months Ended
Mar. 31, 2022 USD ($) loan	Mar. 31, 2021 loan	Dec. 31, 2021 USD ($) loan
Loans and Leases Receivable Disclosure [Line Items]
Number of contracts modified as TDR \| loan	0	7
Current outstanding recorded investment	$ 2,900		$ 3,000
TDR loans \| loan	15		15
Number of Contracts, subsequent default \| loan	0	0
Number of contracts in non-accrual status \| loan	0
Residential \| One- to four-family
Loans and Leases Receivable Disclosure [Line Items]
Number of contracts modified as TDR \| loan	4
Pre-Modification outstanding recorded investment	$ 336
Post-Modification outstanding recorded investment	336
Current outstanding recorded investment	$ 250
Commercial \| Commercial business
Loans and Leases Receivable Disclosure [Line Items]
Number of contracts modified as TDR \| loan	3
Pre-Modification outstanding recorded investment	$ 46
Post-Modification outstanding recorded investment	46
Current outstanding recorded investment	$ 34

Number of contracts in non-accrual status due to delinquency greater than 90 days classified as TDRs.

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Number of financing receivables that have been modified by troubled debt restructurings at reporting date

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

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

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Amount of financing receivable modified as troubled debt restructuring.

+ 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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-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 40
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=121585226&loc=d3e18845-111554

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Number of financing receivable contracts modified as troubled debt restructuring within previous 12 months, with subsequent payment default.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 34
-URI http://asc.fasb.org/extlink&oid=123577603&loc=SL6953682-111524

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