Long Term Subordinated Notes (Schedule Of Outstanding Fixed To Floating Rate Long Term Subordinated Notes) (Details) - USD ($)	6 Months Ended	12 Months Ended
Jun. 30, 2021	Dec. 31, 2020
Debt Instrument [Line Items]
Consolidated Balance Sheet Amount	$ 223,724,000	$ 223,674,000
Subordinated Notes 6.6% [Member] \| Long Term Subordinated Debt [Member]
Debt Instrument [Line Items]
Date Issued	Apr. 26, 2007
Original Principal Amount	$ 400,000,000
Maturity date	May 01, 2067	May 01, 2067
Consolidated Balance Sheet Amount	$ 223,724,000	$ 223,674,000
Market Value	$ 214,772,000	$ 206,447,000
Subordinated Notes 6.6% [Member] \| Long Term Subordinated Debt [Member] \| Scheduled [Member]
Debt Instrument [Line Items]
Maturity date	May 15, 2037
Subordinated Notes 6.6% [Member] \| Long Term Subordinated Debt [Member] \| Final [Member]
Debt Instrument [Line Items]
Maturity date	May 01, 2067

Face (par) amount of debt instrument at time of issuance.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
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Fair value portion of debt instrument payable, including, but not limited to, notes payable and loans payable.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
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Date the debt instrument was issued, in CCYY-MM-DD format.

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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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No definition available.

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Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
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Including the current and noncurrent portions, carrying value as of the balance sheet date of subordinated debt (with initial maturities beyond one year or beyond the operating cycle if longer). Subordinated debt places a lender in a lien position behind debt having a higher priority of repayment in liquidation of the entity's assets.

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