The aggregate fair value of assets that are already posted, at the end of the reporting period, as collateral for derivative instruments with credit-risk-related contingent features.

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Amount of increase in the fair value of derivatives recognized in the income statement.

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

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Derivatives and Hedging Activities - Additional Information (Detail)		12 Months Ended
	Jan. 17, 2023 USD ($)	Dec. 31, 2022 USD ($) Derivative	Dec. 31, 2021 USD ($)
Derivatives Fair Value [Line Items]
Interest rate swaps		$ 761,000	$ 337,000
Cash collateral from counterparties		535,000,000	526,000,000
Interest Rate Swaps [Member] \| Subsequent Event [Member]
Derivatives Fair Value [Line Items]
Gain on derivative	$ 849,000
Designated as Hedging Instrument \| Interest Rate Swaps [Member]
Derivatives Fair Value [Line Items]
Notional amount		10,000,000	10,000,000
Interest rate swaps		761,000,000	37,000,000
Designated as Hedging Instrument \| Interest Rate Swaps [Member] \| Other Assets [Member]
Derivatives Fair Value [Line Items]
Interest rate swap derivative asset		961,000	200,000
Designated as Hedging Instrument \| Interest Rate Swap 2020 [Member]
Derivatives Fair Value [Line Items]
Notional amount		5,000,000	5,000,000
Designated as Hedging Instrument \| Interest Rate Swap 2021 [Member]
Derivatives Fair Value [Line Items]
Notional amount		5,000,000	5,000,000
Cash Flow Hedges on 90-day Advances from FHLB [Member]
Derivatives Fair Value [Line Items]
Other Liabilities		$ 10,000,000	$ 10,000,000
Cash Flow Hedges on 90-day Advances from FHLB [Member] \| Designated as Hedging Instrument \| Interest Rate Swaps [Member]
Derivatives Fair Value [Line Items]
Number of notional interest rate swaps \| Derivative		2
Cash Flow Hedges on 90-day Advances from FHLB [Member] \| Designated as Hedging Instrument \| Interest Rate Swap 2020 [Member]
Derivatives Fair Value [Line Items]
Notional amount		$ 5,000,000
Cash Flow Hedges on 90-day Advances from FHLB [Member] \| Designated as Hedging Instrument \| Interest Rate Swap 2021 [Member]
Derivatives Fair Value [Line Items]
Notional amount		5,000,000
Balance Sheet Hedges on 90-day Advances from FHLB [Member]
Derivatives Fair Value [Line Items]
Other Liabilities		$ 10,000,000.0