Derivative Financial Instruments - Fair Values Instruments (Detail) $ in Thousands	Dec. 31, 2019 USD ($) instrument	Dec. 31, 2018 USD ($) instrument
Derivatives, Fair Value [Line Items]
Notional	$ 502,172	$ 167,933
Derivatives (Fair Value)	966	(2,664)
Derivatives Designated as Hedging Instruments
Derivatives, Fair Value [Line Items]
Notional	75,000	75,000
Derivatives Designated as Hedging Instruments \| Other liabilities
Derivatives, Fair Value [Line Items]
Derivative liabilities, fair value	$ (759)	$ (3,308)
Derivatives Designated as Hedging Instruments \| Interest rate products \| Other liabilities
Derivatives, Fair Value [Line Items]
Number of derivative instruments \| instrument	3	3
Notional	$ 75,000	$ 75,000
Derivative liabilities, fair value	(759)	(3,308)
Derivatives not designated as hedging instruments
Derivatives, Fair Value [Line Items]
Notional	427,172	92,933
Derivatives (Fair Value)	1,725	644
Derivatives not designated as hedging instruments \| Interest rate products \| Other liabilities
Derivatives, Fair Value [Line Items]
Notional	71,804
Derivative liabilities, fair value	(2,688)
Derivatives not designated as hedging instruments \| Interest rate products \| Other assets
Derivatives, Fair Value [Line Items]
Notional	71,804
Derivative assets, fair value	2,520
Derivatives not designated as hedging instruments \| Risk participation agreements \| Other liabilities
Derivatives, Fair Value [Line Items]
Notional	4,524
Derivative liabilities, fair value	(4)
Derivatives not designated as hedging instruments \| Interest rate lock commitments with customers \| Other liabilities
Derivatives, Fair Value [Line Items]
Notional	28,505	6,530
Derivative liabilities, fair value	(191)	(24)
Derivatives not designated as hedging instruments \| Interest rate lock commitments with customers \| Other assets
Derivatives, Fair Value [Line Items]
Notional	99,057	40,795
Derivative assets, fair value	1,768	686
Derivatives not designated as hedging instruments \| Forward sale commitments \| Other liabilities
Derivatives, Fair Value [Line Items]
Notional	90,177	25,876
Derivative liabilities, fair value	(276)	(161)
Derivatives not designated as hedging instruments \| Forward sale commitments \| Other assets
Derivatives, Fair Value [Line Items]
Notional	61,301	19,732
Derivative assets, fair value	$ 596	$ 143

Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset.

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- Definition

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, after the effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

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- Definition

Nominal or face amount used to calculate payment on derivative.

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- Definition

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

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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.

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No definition available.

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