Derivatives and Hedging Activities - Summary of the Company's Derivatives Associated with its Interest Rate Risk Management Activities (Detail) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020
Cash Flow Hedges on 90-day Advances from FHLB [Member]
Derivatives Fair Value [Line Items]
Other Liabilities	$ 10,000	$ 5,000
Designated as Hedging Instrument \| Interest Rate Swap 2020 [Member]
Derivatives Fair Value [Line Items]
Start Date	Apr. 13, 2020	Apr. 13, 2020
Maturity Date	Apr. 13, 2025	Apr. 13, 2025
Rate	0.68%	0.68%
Notional	$ 5,000	$ 5,000
Other Assets	85
Other Liabilities		$ 68
Designated as Hedging Instrument \| Interest Rate Swap 2020 [Member] \| Cash Flow Hedges on 90-day Advances from FHLB [Member]
Derivatives Fair Value [Line Items]
Notional	$ 5,000
Designated as Hedging Instrument \| Interest Rate Swap 2021 [Member]
Derivatives Fair Value [Line Items]
Start Date	Apr. 13, 2021	Apr. 13, 2021
Maturity Date	Apr. 13, 2026	Apr. 13, 2026
Rate	0.74%	0.74%
Notional	$ 5,000	$ 5,000
Other Assets	115
Other Liabilities		69
Designated as Hedging Instrument \| Interest Rate Swap 2021 [Member] \| Cash Flow Hedges on 90-day Advances from FHLB [Member]
Derivatives Fair Value [Line Items]
Notional	5,000
Designated as Hedging Instrument \| Interest Rate Swaps [Member]
Derivatives Fair Value [Line Items]
Notional	10,000	10,000
Other Assets	$ 200
Other Liabilities		$ 137

Date the entity entered into the derivative contract, in YYYY-MM-DD format.

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Fair value of liability arising from contracts that meet the criteria of being accounted for as derivative instruments, financial instrument or contract used to mitigate a specified risk (hedge), energy marketing activities (trading activities), expected to be settled after one year or beyond the normal operating cycle, if longer. Examples of energy marketing activities include, but are not limited to, trading of electricity, coal, natural gas and oil using financial instruments, including, but not limited to, forward contracts, options and swaps.

+ References

No definition available.

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Carrying amount as of the balance sheet date of the assets arising from derivative contracts and hedging activities, which are expected to be converted into cash or otherwise disposed of after a year or beyond the normal operating cycle, if longer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.17)
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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- Definition

Nominal or face amount used to calculate payments on the derivative liability.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1A
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=125515794&loc=SL5579245-113959

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1B
-URI http://asc.fasb.org/extlink&oid=125515794&loc=SL5580258-113959

Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1A
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=125515794&loc=SL5579245-113959

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Date the derivative contract matures, in YYYY-MM-DD format.

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- Definition

Fixed interest rate that will be received or paid upon exercise of the interest rate swaption contract.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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