Derivative Financial Instruments - Summary of Fair Value of Derivative Financial Instruments (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Designated as Hedging Instrument
Derivative [Line Items]
Assets	$ 26,473	$ 17,202
Liabilities	10,342	1,988
Designated as Hedging Instrument \| Cash flow hedges \| Interest rate collars and floors on loan pools
Derivative [Line Items]
Notional	450,000	400,000
Assets	1,559	6,636
Liabilities	459	0
Designated as Hedging Instrument \| Cash flow hedges \| Interest rate swaps on borrowings
Derivative [Line Items]
Notional	150,000	325,000
Assets	3,422	628
Liabilities	0	1,816
Designated as Hedging Instrument \| Fair value hedges \| Interest rate swaps on borrowings
Derivative [Line Items]
Notional	377,500	379,000
Assets	4,976	8,793
Liabilities	0	0
Designated as Hedging Instrument \| Fair value hedges \| Interest rate swaps on investment securities
Derivative [Line Items]
Notional	909,957	347,516
Assets	16,516	1,145
Liabilities	9,883	172
Not Designated as Hedging Instrument
Derivative [Line Items]
Assets	72,514	122,999
Liabilities	16,941	16,199
Not Designated as Hedging Instrument \| Interest rate lock commitments
Derivative [Line Items]
Notional	188,963	224,719
Assets	4,472	9,375
Liabilities	0	0
Not Designated as Hedging Instrument \| Forward mortgage loan contracts
Derivative [Line Items]
Notional	215,238	261,027
Assets	1,305	0
Liabilities	0	2,335
Not Designated as Hedging Instrument \| Customer interest rate swaps
Derivative [Line Items]
Notional	2,384,213	2,008,149
Assets	65,882	113,300
Liabilities	7,202	133
Not Designated as Hedging Instrument \| Counterparty interest rate swaps
Derivative [Line Items]
Notional	2,384,213	2,008,149
Assets	453	0
Liabilities	9,438	13,543
Interest rate contracts net adjustment	50,100	100,400
Not Designated as Hedging Instrument \| Customer foreign currency forward contracts
Derivative [Line Items]
Notional	15,861	9,990
Assets	402	324
Liabilities	0	0
Not Designated as Hedging Instrument \| Counterparty foreign currency forward contracts
Derivative [Line Items]
Notional	15,724	9,854
Assets	0	0
Liabilities	$ 301	$ 188

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

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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- Definition

Nominal or face amount used to calculate payment on derivative.

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