Derivative Financial Instruments Notional Amounts and Fair Values of Derivative Financial Instruments (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	$ 158,647	$ 331,269
Derivative Liability, Fair Value, Gross Liability	(86,327)	(165,210)
Interest Rate Locks with Customers
Derivatives, Fair Value [Line Items]
Derivative Asset, Notional Amount	261,428	382,903
Derivative Liability, Notional Amount	2,549	3,154
Derivative Asset, Fair Value, Gross Asset	2,326	8,034
Derivative Liability, Fair Value, Gross Liability	(23)	(35)
Forward Commitments
Derivatives, Fair Value [Line Items]
Derivative Asset, Notional Amount	51,000	0
Derivative Liability, Notional Amount	0	292,262
Derivative Asset, Fair Value, Gross Asset	41	0
Derivative Liability, Fair Value, Gross Liability	0	(2,263)
Interest Rate Swaps with Customers
Derivatives, Fair Value [Line Items]
Derivative Asset, Notional Amount	3,213,924	3,834,062
Derivative Liability, Notional Amount	752,462	45,640
Derivative Asset, Fair Value, Gross Asset	153,752	330,951
Derivative Liability, Fair Value, Gross Liability	(4,766)	(2)
Interest Rate Swaps with Dealer Counterparties
Derivatives, Fair Value [Line Items]
Derivative Asset, Notional Amount	752,462	45,640
Derivative Liability, Notional Amount	3,213,924	3,834,062
Derivative Asset, Fair Value, Gross Asset	4,766	2
Derivative Liability, Fair Value, Gross Liability	(79,889)	(165,205)
Interest Rate Swaps used in Cash Flow Hedges
Derivatives, Fair Value [Line Items]
Derivative Asset, Notional Amount	500,000	0
Derivative Liability, Notional Amount	500,000	0
Derivative Asset, Fair Value, Gross Asset	60	0
Derivative Liability, Fair Value, Gross Liability	(1,432)	0
Foreign Exchange Contracts with Customers
Derivatives, Fair Value [Line Items]
Derivative Asset, Notional Amount	7,629	1,121
Derivative Liability, Notional Amount	3,388	5,963
Derivative Asset, Fair Value, Gross Asset	229	5
Derivative Liability, Fair Value, Gross Liability	(51)	(275)
Foreign Exchange Contracts with Correspondent Banks
Derivatives, Fair Value [Line Items]
Derivative Asset, Notional Amount	3,656	6,372
Derivative Liability, Notional Amount	9,364	1,422
Derivative Asset, Fair Value, Gross Asset	69	318
Derivative Liability, Fair Value, Gross Liability	$ (240)	$ (5)

Nominal or face amount used to calculate payments on the derivative asset.

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