Investment Securities (Narrative) (Details) $ in Thousands	6 Months Ended	12 Months Ended
	Jun. 30, 2018 USD ($) security financial_institution	Dec. 31, 2009 USD ($)	Dec. 31, 2017 USD ($) security
Schedule of Marketable Securities [Line Items]
Investment securities pledged to secure funds	$ 118,400		$ 98,400
Restricted stock	6,100		1,600
Federal home loan bank, stock	$ 6,000		$ 1,500
Number of corporate trust preferred securities issued | security	171		105
Other than temporary impairment		$ 865
Other-than-temporary impairment loss, debt securities, portion recognized in earnings		364
Other than temporary impairment loss, portion in other comprehensive loss		$ 501
Trust preferred debt securities – single issuer [Member]
Schedule of Marketable Securities [Line Items]
Number of corporate trust preferred securities issued | security	2		4
Number of issuers of corporate trust preferred securities | financial_institution	1
Trust preferred debt securities-pooled [Member]
Schedule of Marketable Securities [Line Items]
Number of issuers of corporate trust preferred securities | financial_institution	2
Atlantic Community Bankers Bank Stock [Member] | Bankers Bank Stock [Member]
Schedule of Marketable Securities [Line Items]
Bankers bank stock	$ 135		$ 65