Derivative Instruments (Fair Value Of Derivative Instruments) (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Customer Counterparties Loan Interest Rate Swap Assets [Member] \| Non-hedging interest rate derivatives: \| Other Assets
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount	$ 45,959	$ 225,480
Derivative, Fair Value	668	4,877
Customer Counterparties Loan Interest Rate Swap Liabilities [Member] \| Non-hedging interest rate derivatives: \| Other Liabilities
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount	458,602	314,450
Derivative, Fair Value	26,163	9,513
Financial Institution Counterparties Loan Interest Rate Swap Asset [Member] \| Non-hedging interest rate derivatives: \| Other Assets
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount	464,569	320,949
Derivative, Fair Value	26,389	9,591
Financial Institution Counterparties Loan Interest Rate Swap Asset [Member] \| Derivatives designated as hedges of fair value: \| Other Assets
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount	3,733	4,326
Derivative, Fair Value	131	34
Financial Institution Counterparties Loan Interest Rate Swap Liabilities [Member] \| Non-hedging interest rate derivatives: \| Other Liabilities
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount	45,959	218,924
Derivative, Fair Value	$ 668	$ 4,877

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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- Definition

Fair value of the assets less the liabilities of a derivative or group of derivatives.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 10
-URI http://asc.fasb.org/extlink&oid=109250915&loc=d3e13433-108611

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- Definition

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+ References

No definition available.

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