Derivatives and Hedging Activities - Fair Value of Derivative Financial Instruments (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Derivatives, Fair Value [Line Items]
Notional Amount	$ 5,133,140	$ 3,624,740
Derivative Asset
Total gross derivative instruments	53,202	50,352
Less: Amounts subject to master netting agreements	(1,444)	(4,683)
Less: Cash collateral received/pledged	(39,841)	(33,921)
Net amount	11,917	11,748
Derivative Liability
Total gross derivative instruments	91,413	84,811
Less: Amounts subject to master netting agreements	(1,444)	(4,683)
Less: Cash collateral received/pledged	(12,593)	(11,330)
Net amount	77,376	68,798
Derivative assets
Derivative Asset
Total gross derivative instruments	53,202	50,352
Derivative liabilities
Derivative Liability
Total gross derivative instruments	91,413	84,811
Designated as hedging instrument
Derivatives, Fair Value [Line Items]
Notional Amount	2,419,520	925,511
Designated as hedging instrument \| Cash flow hedge of subordinated debt
Derivatives, Fair Value [Line Items]
Notional Amount	100,000	100,000
Designated as hedging instrument \| Cash flow hedges of trust preferred securities
Derivatives, Fair Value [Line Items]
Notional Amount	20,000	20,000
Designated as hedging instrument \| Fair value hedges of AFS debt securities
Derivatives, Fair Value [Line Items]
Notional Amount	649,520	655,511
Designated as hedging instrument \| Fair value hedges of loans
Derivatives, Fair Value [Line Items]
Notional Amount	1,650,000	150,000
Designated as hedging instrument \| Derivative assets
Derivative Asset
Derivatives designated as hedging instruments	13,840	13,168
Designated as hedging instrument \| Derivative assets \| Cash flow hedge of subordinated debt
Derivative Asset
Cash flow hedge	13,840	13,168
Designated as hedging instrument \| Derivative assets \| Cash flow hedges of trust preferred securities
Derivative Asset
Cash flow hedge	0	0
Designated as hedging instrument \| Derivative assets \| Fair value hedges of AFS debt securities
Derivative Asset
Fair value hedge	0	0
Designated as hedging instrument \| Derivative assets \| Fair value hedges of loans
Derivative Asset
Fair value hedge	0	0
Designated as hedging instrument \| Derivative liabilities
Derivative Liability
Derivatives designated as hedging instruments	0	0
Designated as hedging instrument \| Derivative liabilities \| Cash flow hedge of subordinated debt
Derivative Liability
Cash flow hedge	0	0
Designated as hedging instrument \| Derivative liabilities \| Cash flow hedges of trust preferred securities
Derivative Liability
Cash flow hedge	0	0
Designated as hedging instrument \| Derivative liabilities \| Fair value hedges of AFS debt securities
Derivative Liability
Fair value hedge	0	0
Designated as hedging instrument \| Derivative liabilities \| Fair value hedges of loans
Derivative Liability
Fair value hedge	0	0
Not designated as hedging instrument
Derivatives, Fair Value [Line Items]
Notional Amount	2,713,620	2,699,229
Not designated as hedging instrument \| Customer derivative positions
Derivatives, Fair Value [Line Items]
Notional Amount	1,173,714	1,177,275
Not designated as hedging instrument \| Dealer offsets to customer derivative positions
Derivatives, Fair Value [Line Items]
Notional Amount	1,173,714	1,197,364
Not designated as hedging instrument \| Risk participations
Derivatives, Fair Value [Line Items]
Notional Amount	89,811	90,597
Not designated as hedging instrument \| Mortgage banking - loan commitments
Derivatives, Fair Value [Line Items]
Notional Amount	67,260	48,452
Not designated as hedging instrument \| Mortgage banking - forward sales commitment
Derivatives, Fair Value [Line Items]
Notional Amount	105,251	81,671
Not designated as hedging instrument \| Bifurcated embedded derivatives
Derivatives, Fair Value [Line Items]
Notional Amount	51,935	51,935
Not designated as hedging instrument \| Dealer offsets to bifurcated embedded derivatives
Derivatives, Fair Value [Line Items]
Notional Amount	51,935	51,935
Not designated as hedging instrument \| Derivative assets
Derivative Asset
Derivatives not designated as hedging instruments	39,362	37,184
Not designated as hedging instrument \| Derivative assets \| Customer derivative positions
Derivative Asset
Derivatives not designated as hedging instruments	1,358	3,461
Not designated as hedging instrument \| Derivative assets \| Dealer offsets to customer derivative positions
Derivative Asset
Derivatives not designated as hedging instruments	25,588	23,061
Not designated as hedging instrument \| Derivative assets \| Risk participations
Derivative Asset
Derivatives not designated as hedging instruments	1	1
Not designated as hedging instrument \| Derivative assets \| Mortgage banking - loan commitments
Derivative Asset
Derivatives not designated as hedging instruments	1,630	1,089
Not designated as hedging instrument \| Derivative assets \| Mortgage banking - forward sales commitment
Derivative Asset
Derivatives not designated as hedging instruments	89	20
Not designated as hedging instrument \| Derivative assets \| Bifurcated embedded derivatives
Derivative Asset
Derivatives not designated as hedging instruments	10,696	9,552
Not designated as hedging instrument \| Derivative assets \| Dealer offsets to bifurcated embedded derivatives
Derivative Asset
Derivatives not designated as hedging instruments	0	0
Not designated as hedging instrument \| Derivative liabilities
Derivative Liability
Derivatives not designated as hedging instruments	91,413	84,811
Not designated as hedging instrument \| Derivative liabilities \| Customer derivative positions
Derivative Liability
Derivatives not designated as hedging instruments	77,635	68,384
Not designated as hedging instrument \| Derivative liabilities \| Dealer offsets to customer derivative positions
Derivative Liability
Derivatives not designated as hedging instruments	1,337	4,597
Not designated as hedging instrument \| Derivative liabilities \| Risk participations
Derivative Liability
Derivatives not designated as hedging instruments	6	8
Not designated as hedging instrument \| Derivative liabilities \| Mortgage banking - loan commitments
Derivative Liability
Derivatives not designated as hedging instruments	0	0
Not designated as hedging instrument \| Derivative liabilities \| Mortgage banking - forward sales commitment
Derivative Liability
Derivatives not designated as hedging instruments	180	658
Not designated as hedging instrument \| Derivative liabilities \| Bifurcated embedded derivatives
Derivative Liability
Derivatives not designated as hedging instruments	0	0
Not designated as hedging instrument \| Derivative liabilities \| Dealer offsets to bifurcated embedded derivatives
Derivative Liability
Derivatives not designated as hedging instruments	$ 12,255	$ 11,164

Fair value of securities received as collateral against derivative assets.

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