Income Taxes Components of Deferred Tax Assets and Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Deferred Tax Assets:
Allowance for Loan Losses	$ 7,472	$ 5,383
Lease liabilities	2,717	2,787
Pension and Deferred Compensation Plans	3,149	2,923
Pension Liability Included in Accumulated Other Comprehensive Income	2,439	2,329
Historic Tax Credit	1,394	0
Other	385	352
Total Gross Deferred Tax Assets	17,556	13,774
Valuation Allowance for Deferred Tax Assets	0	0
Total Gross Deferred Tax Assets, Net of Valuation Allowance	17,556	13,774
Deferred Tax Liabilities:
Pension Plans	5,368	5,270
Depreciation	3,018	1,943
ROU assets	2,638	2,748
Deferred Income	2,327	3,215
Net Unrealized Gains on Equity Securities	132	240
Net Unrealized Gains on Securities Available-for-Sale Included in Accumulated Other Comprehensive Income	1,991	160
Goodwill	3,474	3,502
Gain on Cash Flow Hedge Agreements	166	0
Total Gross Deferred Tax Liabilities	19,114	17,078
Deferred Tax Liability, Net	$ 1,558	$ 3,304