Summary Of Significant Accounting Policies (Narrative) (Details) $ in Millions	12 Months Ended
Dec. 31, 2017 USD ($) contracts	Dec. 31, 2016 USD ($) contracts
Lease term	7 years
Other real estate owned	$ 40.6	$ 40.3
Bank-owned life insurance	$ 145.9	$ 141.6
Number of covered call option contracts outstanding \| contracts	0	0
Excess tax benefit	$ 6.2
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	15 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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