Summary Of Significant Accounting Policies (Narrative) (Details) $ in Millions	12 Months Ended
Dec. 31, 2016 USD ($) contracts	Dec. 31, 2015 USD ($) contracts
Lease term	7 years
Other real estate owned	$ 40.3	$ 43.9
Bank-owned life insurance	$ 141.6	$ 136.2
Number of covered call option contracts outstanding \| contracts	0	0
Debt issuance costs		$ 7.8
Land Improvements
Premises and equipment, useful lives	15 years
Minimum
Tax benefit realized on settlement, percentage	50.00%
Minimum \| Furniture, Fixtures and Equipment
Premises and equipment, useful lives	2 years
Minimum \| Software and Computer-Related Equipment
Premises and equipment, useful lives		2 years
Minimum \| Buildings and Improvements
Premises and equipment, useful lives	7 years
Maximum
Finite-lived intangibles, useful life	20 years
Maximum \| Furniture, Fixtures and Equipment
Premises and equipment, useful lives	12 years
Maximum \| Software and Computer-Related Equipment
Premises and equipment, useful lives		5 years
Maximum \| Buildings and Improvements
Premises and equipment, useful lives	39 years

The carrying amount of a life insurance policy on an officer, executive or employee for which the reporting entity (a bank) is entitled to proceeds from the policy upon death of the insured or surrender of the insurance policy.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.10)
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Term of the lessor's leasing arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Carrying amount of other real estate not covered by loss sharing agreements not separately disclosed, including, but not limited to, real estate investments, real estate loans that qualify as investments in real estate, and premises that are no longer used in operations that may also be included in real estate owned. Excludes real estate assets taken in settlement of troubled loans through surrender or foreclosure by banks.

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The remaining balance of debt issuance expenses that were capitalized and are being amortized against income over the lives of the respective bond issues. This does not include the amounts capitalized as part of the cost of the utility plant or asset.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.17)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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Number of covered call option contracts outstanding

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