Income Taxes Components of Deferred Tax Assets and Liabilities (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Deferred Tax Assets, Gross [Abstract]
Allowance for Loan Losses	$ 6,113	$ 5,794
Pension and Deferred Compensation Plans	3,885	3,999
Pension Liability Included in Accumulated Other Comprehensive Income	6,263	4,426
Other	614	566
Total Gross Deferred Tax Assets	16,875us-gaap_DeferredTaxAssetsGross	14,785us-gaap_DeferredTaxAssetsGross
Valuation Allowance for Deferred Tax Assets	0	0
Total Gross Deferred Tax Assets, Net of Valuation Allowance	16,875us-gaap_DeferredTaxAssetsNet	14,785us-gaap_DeferredTaxAssetsNet
Deferred Tax Liabilities, Gross [Abstract]
Pension Plans	7,604	7,724
Depreciation	1,222	1,561
Deferred Income	3,927	3,526
Net Unrealized Gains on Securities Available-for-Sale Included in Accumulated Other Comprehensive Income	1,638	1,557
Goodwill	5,242	5,230
Total Gross Deferred Tax Liabilites	$ 19,633us-gaap_DeferredTaxLiabilities	$ 19,598us-gaap_DeferredTaxLiabilities

Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards.

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