Loans and Allowance for Loan Losses - Schedule of Troubled Debt Restructuring (Detail) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2022 USD ($) Office Lease Contract	Dec. 31, 2021 USD ($) Office Lease Contract
Financing Receivable Modifications [Line Items]
Number of Contracts \| Contract	14	15
TDRs Listed as Accrual	$ 2,111	$ 2,228
Trouble Debt Restructurings Listed As Accrual
Financing Receivable Modifications [Line Items]
Number of Contracts \| Office	11	11
TDRs Listed as Accrual	$ 1,193	$ 1,200
Trouble Debt Restructurings Listed As Non Accrual
Financing Receivable Modifications [Line Items]
Number of Contracts \| Lease	3	4
TDRs Listed as Accrual	$ 918	$ 1,028
Residential Real Estate [Member] \| One-to-Four Family [Member]
Financing Receivable Modifications [Line Items]
Number of Contracts \| Contract	12	12
TDRs Listed as Accrual	$ 2,015	$ 2,022
Residential Real Estate [Member] \| Home Equity Loans and Lines of Credit [Member]
Financing Receivable Modifications [Line Items]
Number of Contracts \| Contract	2	3
TDRs Listed as Accrual	$ 96	$ 206
Residential Real Estate [Member] \| Trouble Debt Restructurings Listed As Accrual \| One-to-Four Family [Member]
Financing Receivable Modifications [Line Items]
Number of Contracts \| Office	9	9
TDRs Listed as Accrual	$ 1,097	$ 1,103
Residential Real Estate [Member] \| Trouble Debt Restructurings Listed As Accrual \| Home Equity Loans and Lines of Credit [Member]
Financing Receivable Modifications [Line Items]
Number of Contracts \| Office	2	2
TDRs Listed as Accrual	$ 96	$ 97
Residential Real Estate [Member] \| Trouble Debt Restructurings Listed As Non Accrual \| One-to-Four Family [Member]
Financing Receivable Modifications [Line Items]
Number of Contracts \| Lease	3	3
TDRs Listed as Accrual	$ 918	$ 919
Residential Real Estate [Member] \| Trouble Debt Restructurings Listed As Non Accrual \| Home Equity Loans and Lines of Credit [Member]
Financing Receivable Modifications [Line Items]
Number of Contracts \| Lease		1
TDRs Listed as Accrual		$ 109

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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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