Derivatives and Hedging Activities - Fair value of derivative financial instruments (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Derivatives, Fair Value [Line Items]
Notional Amount	$ 3,052,601	$ 3,529,643
Derivative Assets
Total gross derivative instruments	42,480	86,666
Less: Amounts subject to master netting agreements	(694)	(114)
Less: Cash collateral received/pledged	(6,620)	(3,200)
Net amount	35,166	83,352
Derivative Liabilities
Total gross derivative instruments	25,145	29,003
Less: Amounts subject to master netting agreements	(694)	(114)
Less: Cash collateral received/pledged	(14,148)	(27,092)
Net amount	10,303	1,797
Derivative assets
Derivative Assets
Total gross derivative instruments	42,480	86,666
Derivative liabilities
Derivative Liabilities
Total gross derivative instruments	25,145	29,003
Designated as hedging instrument
Derivatives, Fair Value [Line Items]
Notional Amount	130,000	140,000
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 hedge of trust preferred securities
Derivatives, Fair Value [Line Items]
Notional Amount	20,000	20,000
Designated as hedging instrument \| Fair value hedge of brokered CDs
Derivatives, Fair Value [Line Items]
Notional Amount	10,000	20,000
Designated as hedging instrument \| Derivative assets
Derivative Assets
Derivatives designated as hedging instruments	6,389	3,378
Designated as hedging instrument \| Derivative assets \| Cash flow hedge of subordinated debt
Derivative Assets
Cash flow hedge	6,389	3,378
Designated as hedging instrument \| Derivative assets \| Cash flow hedge of trust preferred securities
Derivative Assets
Cash flow hedge	0	0
Designated as hedging instrument \| Derivative assets \| Fair value hedge of brokered CDs
Derivative Assets
Fair value hedge	0	0
Designated as hedging instrument \| Derivative liabilities
Derivative Liabilities
Derivatives designated as hedging instruments	0	0
Designated as hedging instrument \| Derivative liabilities \| Cash flow hedge of subordinated debt
Derivative Liabilities
Cash flow hedge	0	0
Designated as hedging instrument \| Derivative liabilities \| Cash flow hedge of trust preferred securities
Derivative Liabilities
Cash flow hedge	0	0
Designated as hedging instrument \| Derivative liabilities \| Fair value hedge of brokered CDs
Derivative Liabilities
Fair value hedge	0	0
Not designated as hedging instrument
Derivatives, Fair Value [Line Items]
Notional Amount	2,922,601	3,389,643
Not designated as hedging instrument \| Customer derivative positions
Derivatives, Fair Value [Line Items]
Notional Amount	1,206,145	1,329,271
Not designated as hedging instrument \| Dealer offsets to customer derivative positions
Derivatives, Fair Value [Line Items]
Notional Amount	1,230,885	1,329,271
Not designated as hedging instrument \| Risk participations
Derivatives, Fair Value [Line Items]
Notional Amount	69,385	48,843
Not designated as hedging instrument \| Mortgage banking - loan commitment
Derivatives, Fair Value [Line Items]
Notional Amount	110,897	253,243
Not designated as hedging instrument \| Mortgage banking - forward sales commitment
Derivatives, Fair Value [Line Items]
Notional Amount	201,419	325,145
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 Assets
Derivatives not designated as hedging instruments	36,091	83,288
Not designated as hedging instrument \| Derivative assets \| Customer derivative positions
Derivative Assets
Derivatives not designated as hedging instruments	28,656	72,508
Not designated as hedging instrument \| Derivative assets \| Dealer offsets to customer derivative positions
Derivative Assets
Derivatives not designated as hedging instruments	974	1
Not designated as hedging instrument \| Derivative assets \| Risk participations
Derivative Assets
Derivatives not designated as hedging instruments	16	28
Not designated as hedging instrument \| Derivative assets \| Mortgage banking - loan commitment
Derivative Assets
Derivatives not designated as hedging instruments	3,450	10,751
Not designated as hedging instrument \| Derivative assets \| Mortgage banking - forward sales commitment
Derivative Assets
Derivatives not designated as hedging instruments	67	0
Not designated as hedging instrument \| Derivative assets \| Bifurcated embedded derivatives
Derivative Assets
Derivatives not designated as hedging instruments	2,928	0
Not designated as hedging instrument \| Derivative assets \| Dealer offsets to bifurcated embedded derivatives
Derivative Assets
Derivatives not designated as hedging instruments	0	0
Not designated as hedging instrument \| Derivative liabilities
Derivative Liabilities
Derivatives not designated as hedging instruments	25,145	29,003
Not designated as hedging instrument \| Derivative liabilities \| Customer derivative positions
Derivative Liabilities
Derivatives not designated as hedging instruments	10,663	17
Not designated as hedging instrument \| Derivative liabilities \| Dealer offsets to customer derivative positions
Derivative Liabilities
Derivatives not designated as hedging instruments	9,232	24,614
Not designated as hedging instrument \| Derivative liabilities \| Risk participations
Derivative Liabilities
Derivatives not designated as hedging instruments	7	12
Not designated as hedging instrument \| Derivative liabilities \| Mortgage banking - loan commitment
Derivative Liabilities
Derivatives not designated as hedging instruments	0	0
Not designated as hedging instrument \| Derivative liabilities \| Mortgage banking - forward sales commitment
Derivative Liabilities
Derivatives not designated as hedging instruments	202	1,964
Not designated as hedging instrument \| Derivative liabilities \| Bifurcated embedded derivatives
Derivative Liabilities
Derivatives not designated as hedging instruments	0	1,449
Not designated as hedging instrument \| Derivative liabilities \| Dealer offsets to bifurcated embedded derivatives
Derivative Liabilities
Derivatives not designated as hedging instruments	$ 5,041	$ 947

Fair value of securities received as collateral against derivative assets.

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