Derivative Instruments (Impact Of Derivatives On Balance Sheet) (Details) - Not Designated As Hedging Instruments - USD ($)	Dec. 31, 2018	Dec. 31, 2017
Derivative [Line Items]
Fair Value of Derivative Assets	$ 19,332,000	$ 11,722,000
Fair Value of Derivative Liabilities	18,208,000	17,097,000
Interest rate contracts
Derivative [Line Items]
Notional Amount	1,840,288,000	1,466,059,000
Fair Value of Derivative Assets	18,388,000	10,786,000
Fair Value of Derivative Liabilities	15,716,000	12,638,000
Mortgage derivatives \| Interest Rate Lock Commitments
Derivative [Line Items]
Notional Amount	52,420,000	49,304,000
Fair Value of Derivative Assets	944,000	936,000
Fair Value of Derivative Liabilities	0	0
Mortgage derivatives \| Forward commitments to sell fixed-rate mortgage loans
Derivative [Line Items]
Notional Amount	65,500,000	72,500,000
Fair Value of Derivative Assets	0	0
Fair Value of Derivative Liabilities	819,000	129,000
Visa Derivative
Derivative [Line Items]
Fair Value of Derivative Assets	0	0
Fair Value of Derivative Liabilities	$ 1,673,000	$ 4,330,000

Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 12
-Section 13
-Sentence Column B

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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.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 50
-Paragraph 3
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-URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312

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-Subparagraph (c)
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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.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
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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.

+ References

No definition available.

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