Basis of Presentation (Non-Interest Income Including Revenue From Contracts With Customers In Scope Of ASU 2014-09) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Total non-interest income	$ 1,274	$ 1,273
Total Revenue Not Within the Scope of ASC 606 [Member]
Revenue from contracts with customers	167	154
Revenue from Contracts with Customers in Scope of ASU 2014-09 [Member]
Revenue from contracts with customers	1,107	1,119
Revenue from Contracts with Customers in Scope of ASU 2014-09 [Member] | Service Charges [Member]
Revenue from contracts with customers	291	313
Revenue from Contracts with Customers in Scope of ASU 2014-09 [Member] | Service Charges Non-Sufficient Funds Charges [Member]
Revenue from contracts with customers	133	159
Revenue from Contracts with Customers in Scope of ASU 2014-09 [Member] | Service Charges Business Analysis Charges [Member]
Revenue from contracts with customers	46	41
Revenue from Contracts with Customers in Scope of ASU 2014-09 [Member] | Service Charges Cycle Charges [Member
Revenue from contracts with customers	20	23
Revenue from Contracts with Customers in Scope of ASU 2014-09 [Member] | Service Charges Lockbox Fees [Member]
Revenue from contracts with customers	47	44
Revenue from Contracts with Customers in Scope of ASU 2014-09 [Member] | Service Charges Stop Payment Fees [Member]
Revenue from contracts with customers	4	4
Revenue from Contracts with Customers in Scope of ASU 2014-09 [Member] | Service Charges Wire Transfer Fees [Member]
Revenue from contracts with customers	22	21
Revenue from Contracts with Customers in Scope of ASU 2014-09 [Member] | Service Charges Other Service Charges [Member]
Revenue from contracts with customers	19	21
Revenue from Contracts with Customers in Scope of ASU 2014-09 [Member] | Wealth Management [Member]
Revenue from contracts with customers	445	435
Revenue from Contracts with Customers in Scope of ASU 2014-09 [Member] | Wealth Management DNB Investments & Insurance [Member]
Revenue from contracts with customers	76	89
Revenue from Contracts with Customers in Scope of ASU 2014-09 [Member] | Wealth Management DNB First Investment Management & Trust [Member]
Revenue from contracts with customers	369	346
Revenue from Contracts with Customers in Scope of ASU 2014-09 [Member] | Other Fee Income [Member]
Revenue from contracts with customers	371	371
Revenue from Contracts with Customers in Scope of ASU 2014-09 [Member] | Other Fee Income Cardholder Interchange Fees [Member]
Revenue from contracts with customers	253	245
Revenue from Contracts with Customers in Scope of ASU 2014-09 [Member] | Other Fee Income Safe Deposit Box [Member]
Revenue from contracts with customers	23	24
Revenue from Contracts with Customers in Scope of ASU 2014-09 [Member] | Other Fee Income Check Printing [Member]
Revenue from contracts with customers	24	23
Revenue from Contracts with Customers in Scope of ASU 2014-09 [Member] | Other Fee Income Merchant Card Processing [Member]
Revenue from contracts with customers	42	48
Revenue from Contracts with Customers in Scope of ASU 2014-09 [Member] | Other Fee Income ATM Surcharges For Non-DNB Customers [Member]
Revenue from contracts with customers	15	17
Revenue from Contracts with Customers in Scope of ASU 2014-09 [Member] | Other Fee Income Other Fee [Member]
Revenue from contracts with customers	$ 14	$ 14