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Derivative Financial Instruments - Summary of Fair Value of Derivative Financial Instruments (Detail) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Designated as Hedging Instrument
Derivative [Line Items]
Assets	$ 63,407	$ 17,202
Liabilities	0	1,988
Designated as Hedging Instrument | Cash flow hedges | Interest rate collars and floors on loan pools
Derivative [Line Items]
Notional	400,000	400,000
Assets	4,830	6,636
Liabilities	0	0
Designated as Hedging Instrument | Cash flow hedges | Interest rate swaps on borrowings
Derivative [Line Items]
Notional	150,000	325,000
Assets	4,548	628
Liabilities	0	1,816
Designated as Hedging Instrument | Fair value hedges | Interest rate swaps on borrowings
Derivative [Line Items]
Notional	379,000	379,000
Assets	7,218	8,793
Liabilities	0	0
Designated as Hedging Instrument | Fair value hedges | Interest rate swaps on investment securities
Derivative [Line Items]
Notional	884,957	347,516
Assets	46,811	1,145
Liabilities	0	172
Not Designated as Hedging Instrument
Derivative [Line Items]
Assets	75,037	122,999
Liabilities	23,700	16,199
Not Designated as Hedging Instrument | Interest rate lock commitments
Derivative [Line Items]
Notional	237,439	224,719
Assets	5,454	9,375
Liabilities	0	0
Not Designated as Hedging Instrument | Forward mortgage loan contracts
Derivative [Line Items]
Notional	273,710	261,027
Assets	4,847	0
Liabilities	0	2,335
Not Designated as Hedging Instrument | Customer interest rate swaps
Derivative [Line Items]
Notional	2,098,087	2,008,149
Assets	63,403	113,300
Liabilities	14,715	133
Not Designated as Hedging Instrument | Counterparty interest rate swaps
Derivative [Line Items]
Notional	2,098,087	2,008,149
Assets	778	0
Liabilities	8,602	13,543
Interest rate contracts net adjustment	41,200	100,400
Not Designated as Hedging Instrument | Customer foreign currency forward contracts
Derivative [Line Items]
Notional	22,849	9,990
Assets	555	324
Liabilities	0	0
Not Designated as Hedging Instrument | Counterparty foreign currency forward contracts
Derivative [Line Items]
Notional	22,644	9,854
Assets	0	0
Liabilities	$ 383	$ 188

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- Definition

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.

+ References

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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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Nominal or face amount used to calculate payment on derivative.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
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-Topic 815
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