Loans and Asset Quality Information (Schedule of Applied Cost Recovery Method of Purchased Impaired Loans) (Details) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
	Jun. 30, 2018	Dec. 31, 2017
Purchased Credit Impaired Loans (substantially all of which are covered loans)
Balance, beginning, carrying value	$ 23,165	$ 514
Change due to payments received and accretion	(2,328)	(6,016)
Change due to loan charge-offs	(10)	(12)
Transfers to foreclosed real estate		(69)
Other	5	(392)
Balance, ending, carrying value	20,832	23,165
Carolina Bank [Member]
Purchased Credit Impaired Loans (substantially all of which are covered loans)
Additions due to acquisition		19,254
Asheville Savings Bank [Member]
Purchased Credit Impaired Loans (substantially all of which are covered loans)
Additions due to acquisition		9,886
Accretable Yield for PCI loans [Member]
Purchased Credit Impaired Loans (substantially all of which are covered loans)
Balance, beginning, carrying value	4,688
Accretion	(784)	(1,846)
Reclassification from (to) nonaccretable difference	206	423
Other	48	690
Balance, ending, carrying value	4,158	4,688
Accretable Yield for PCI loans [Member] | Carolina Bank [Member]
Purchased Credit Impaired Loans (substantially all of which are covered loans)
Additions due to acquisition		3,617
Accretable Yield for PCI loans [Member] | Asheville Savings Bank [Member]
Purchased Credit Impaired Loans (substantially all of which are covered loans)
Additions due to acquisition		$ 1,804