Derivative Instruments and Hedging Activities (Impact of Derivatives on Balance Sheet) (Details) - USD ($)	Mar. 31, 2021	Dec. 31, 2020
Derivatives not designated as hedging instruments
Derivative [Line Items]
Fair Value of Derivative Assets	$ 220,958,000	$ 320,493,000
Fair Value of Derivative Liabilities	132,608,000	157,167,000
Derivatives not designated as hedging instruments \| Interest rate contracts
Derivative [Line Items]
Notional Amount	8,891,025,000	8,784,141,000
Fair Value of Derivative Assets	211,787,000	314,234,000
Fair Value of Derivative Liabilities	130,737,000	153,204,000
Derivatives not designated as hedging instruments \| Mortgage derivatives \| Mortgage derivatives - interest rate lock commitments
Derivative [Line Items]
Notional Amount	284,662,000	306,138,000
Fair Value of Derivative Assets	4,540,000	6,259,000
Fair Value of Derivative Liabilities	0	0
Derivatives not designated as hedging instruments \| Mortgage derivatives \| Mortgage derivatives - forward commitments to sell fixed-rate mortgage loans
Derivative [Line Items]
Notional Amount	298,000,000	230,500,000
Fair Value of Derivative Assets	4,631,000	0
Fair Value of Derivative Liabilities	0	1,611,000
Derivatives not designated as hedging instruments \| Other contracts
Derivative [Line Items]
Notional Amount	170,131,000	234,884,000
Fair Value of Derivative Assets	0	0
Fair Value of Derivative Liabilities	103,000	304,000
Derivatives not designated as hedging instruments \| Visa derivative
Derivative [Line Items]
Notional Amount	0	0
Fair Value of Derivative Assets	0	0
Fair Value of Derivative Liabilities	1,768,000	2,048,000
Derivatives not designated as hedging instruments \| Risk derivative
Derivative [Line Items]
Notional Amount	2,500,000	2,600,000
Cash flow hedges
Derivative [Line Items]
Fair Value of Derivative Assets	55,873,000	80,802,000
Fair Value of Derivative Liabilities	4,885,000	0
Cash flow hedges \| Interest rate contracts
Derivative [Line Items]
Notional Amount	3,250,000,000	3,000,000,000
Fair Value of Derivative Assets	55,873,000	80,802,000
Fair Value of Derivative Liabilities	$ 4,885,000	$ 0

Fair value, after offset of derivative liability, of 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, before offset against an obligation to return collateral under a master netting arrangement. Includes assets elected not to be offset. Excludes assets not subject to a master netting arrangement.

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- Definition

Fair value, after offset of derivative asset, of 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, elected not to be and before offset against a right to receive collateral under a master netting arrangement. Includes liabilities elected not to be offset. Excludes liabilities not subject to a master netting arrangement.

+ References

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-Publisher FASB
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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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- Definition

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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