Derivative Instruments (Fair Value Of Derivative Instruments) (Details) - Non-hedging interest rate derivatives: - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Customer Counterparties Loan Interest Rate Swap Assets \| Other Assets
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount	$ 610,508	$ 377,534
Derivative, Fair Value	60,886	16,094
Customer Counterparties Loan Interest Rate Swap Liabilities \| Other Liabilities
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount	13,907	189,803
Derivative, Fair Value	1,232	3,214
Financial Institution Counterparties Loan Interest Rate Swap Asset \| Other Assets
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount	13,907	189,803
Derivative, Fair Value	1,232	3,214
Financial Institution Counterparties Loan Interest Rate Swap Liabilities \| Other Liabilities
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount	615,348	382,566
Derivative, Fair Value	$ 61,091	$ 16,133

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

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=121572278&loc=d3e13433-108611

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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
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1B
-URI http://asc.fasb.org/extlink&oid=121590274&loc=SL5580258-113959

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1A
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=121590274&loc=SL5579245-113959

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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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