Derivative Instruments (Fair Value Of Derivative Instruments) (Details) - Non-hedging interest rate derivatives: - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Customer Counterparties Loan Interest Rate Swap Assets \| Other Assets
Derivatives, Fair Value [Line Items]
Notional Amount	$ 519,841	$ 647,613
Fair Value	23,299	52,364
Customer Counterparties Loan Interest Rate Swap Liabilities \| Other Liabilities
Derivatives, Fair Value [Line Items]
Notional Amount	167,663	37,721
Fair Value	6,250	562
Financial Institution Counterparties Loan Interest Rate Swap Asset \| Other Assets
Derivatives, Fair Value [Line Items]
Notional Amount	177,540	37,721
Fair Value	6,677	562
Financial Institution Counterparties Loan Interest Rate Swap Liabilities \| Other Liabilities
Derivatives, Fair Value [Line Items]
Notional Amount	523,894	661,866
Fair Value	$ 23,433	$ 52,607

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

+ Details

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Balance Type:	debit
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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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