Derivative Financial Instruments - Fair Values Instruments (Detail) $ in Thousands	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($) instrument
Derivatives, Fair Value [Line Items]
Notional	$ 801,542	$ 502,172
Derivatives (Fair Value)	(17,809)	966
Derivatives Designated as Hedging Instruments
Derivatives, Fair Value [Line Items]
Notional		75,000
Derivatives Designated as Hedging Instruments \| Other Liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative liabilities, fair value		$ 759
Derivatives Designated as Hedging Instruments \| Interest rate products \| Other Liabilities [Member]
Derivatives, Fair Value [Line Items]
Number of derivative instruments \| instrument		3
Notional		$ 75,000
Derivative liabilities, fair value		759
Derivatives not designated as hedging instruments
Derivatives, Fair Value [Line Items]
Notional		427,172
Derivative assets, fair value		1,725
Derivatives not designated as hedging instruments \| Interest rate products \| Other Assets [Member]
Derivatives, Fair Value [Line Items]
Notional	61,326	71,804
Derivative assets, fair value	5,369	2,520
Derivatives not designated as hedging instruments \| Interest rate products \| Other Liabilities [Member]
Derivatives, Fair Value [Line Items]
Notional	61,326	71,804
Derivative liabilities, fair value	(5,851)	(2,688)
Derivatives not designated as hedging instruments \| Risk participation agreements \| Other Liabilities [Member]
Derivatives, Fair Value [Line Items]
Notional	4,372	4,524
Derivative liabilities, fair value	(10)	(4)
Derivatives not designated as hedging instruments \| Interest rate lock commitments with customers \| Other Assets [Member]
Derivatives, Fair Value [Line Items]
Notional	244,037	99,057
Derivative assets, fair value	8,496	1,768
Derivatives not designated as hedging instruments \| Interest rate lock commitments with customers \| Other Liabilities [Member]
Derivatives, Fair Value [Line Items]
Notional	8,413	28,505
Derivative liabilities, fair value	(117)	(191)
Derivatives not designated as hedging instruments \| Forward sale commitments \| Other Assets [Member]
Derivatives, Fair Value [Line Items]
Notional	50,705	61,301
Derivative assets, fair value	583	596
Derivatives not designated as hedging instruments \| Forward sale commitments \| Other Liabilities [Member]
Derivatives, Fair Value [Line Items]
Notional	258,186	90,177
Derivative liabilities, fair value	(2,240)	$ (276)
Derivatives not designated as hedging instruments \| Financial derivative related to sales of certain Visa Class B shares \| Other Liabilities [Member]
Derivatives, Fair Value [Line Items]
Notional	113,177
Derivative liabilities, fair value	$ (24,039)

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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- Definition

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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