Derivative Financial Instruments - Additional Information (Detail) $ in Thousands	12 Months Ended
Dec. 31, 2020 USD ($) institution loan instrument	Dec. 31, 2019 USD ($) transaction loan
Derivatives, Fair Value [Line Items]
Number of instruments terminated \| instrument	3
Termination value of derivatives	$ (17,809)	$ 966
Interest rate cash flow hedge increase decrease interest expense to be reclassified during next 12 months (less than)	500
Interest rate cash flow hedge gain (loss) reclassified to earnings, net	$ (400)
Number of unrelated financial institutions \| institution	4
Derivative transaction held for guarantee \| loan	234	172
Notional	$ 801,542	$ 502,172
Minimum
Derivatives, Fair Value [Line Items]
Notional amount maturity period	1 year
Maximum
Derivatives, Fair Value [Line Items]
Notional amount maturity period	15 years
Interest Rate Swap
Derivatives, Fair Value [Line Items]
Derivative transaction held for guarantee	231	156
Notional	$ 1,100,000	$ 941,000
Aggregate fair value of swaps to customers	81,600	27,400
Swap Guarantee
Derivatives, Fair Value [Line Items]
Aggregate fair value of swaps to customers	12,800	$ 8,800
Cash
Derivatives, Fair Value [Line Items]
Collateral value against obligations	7,400
Other Security Investments
Derivatives, Fair Value [Line Items]
Collateral value against obligations	7,400
Accrued Liabilities
Derivatives, Fair Value [Line Items]
Termination value of derivatives	$ 1,300

Fair value of securities received as collateral against derivative assets.

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Fair values as of the balance sheet date of the net amount of all assets and liabilities resulting from contracts that meet the criteria of being accounted for as derivative instruments.

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Fair value as of the balance sheet date of derivative instrument not designated as hedging instrument and classified as a liability.

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The number of derivative instruments of a particular derivative liability or group of derivative liabilities held by the entity.

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Nominal or face amount used to calculate payment on derivative.

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Period remaining until the derivative contract matures, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The amount of net gains or losses on interest rate cash flow hedges reclassified during the period to earnings from accumulated other comprehensive income upon the hedged transaction affecting earnings.

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The estimated net amount of unrealized gains or losses on interest rate cash flow hedges as of the balance sheet date expected to be reclassified to earnings within the next twelve months.

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Derivative , Number Of Instruments Terminated

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Number Of Financial Institutions

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