Note 5 - Allowance for Loan Losses - Allowance for Loan Losses on PCI Loans and Recorded Investment (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Acquired impaired loans evaluated for impairment	$ 16,181	$ 18,440
Allowance for acquired impaired loans
Commercial Portfolio Segment [Member]
Acquired impaired loans evaluated for impairment	6,732	5,329
Allowance for acquired impaired loans
Commercial Portfolio Segment [Member] | Waccamaw Commercial [Member]
Acquired impaired loans evaluated for impairment	1,330	64
Allowance for acquired impaired loans
Commercial Portfolio Segment [Member] | Peoples Commercial [Member]
Acquired impaired loans evaluated for impairment	4,479	4,279
Allowance for acquired impaired loans
Commercial Portfolio Segment [Member] | Other Commercial Loan [Member]
Acquired impaired loans evaluated for impairment	923	986
Allowance for acquired impaired loans
Consumer Real Estate Portfolio Segment [Member]
Acquired impaired loans evaluated for impairment	9,449	13,111
Allowance for acquired impaired loans
Consumer Real Estate Portfolio Segment [Member] | Waccamaw Serviced Home Equity Lines [Member]
Acquired impaired loans evaluated for impairment	7,662	11,118
Allowance for acquired impaired loans
Consumer Real Estate Portfolio Segment [Member] | Waccamaw Residential [Member]
Acquired impaired loans evaluated for impairment	823	994
Allowance for acquired impaired loans
Consumer Real Estate Portfolio Segment [Member] | Peoples Residential [Member]
Acquired impaired loans evaluated for impairment	964	999
Allowance for acquired impaired loans