Note 6 - Allowance for Loan Losses - Allowance for Loan Losses on PCI Loans and Recorded Investment (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Acquired impaired loans evaluated for impairment	$ 39,662	$ 61,247
Allowance for acquired impaired loans	0	0
Commercial Portfolio Segment [Member]
Acquired impaired loans evaluated for impairment	25,804	41,167
Allowance for acquired impaired loans	0	0
Commercial Portfolio Segment [Member] | Waccamaw Commercial [Member]
Acquired impaired loans evaluated for impairment	0	0
Allowance for acquired impaired loans	0	0
Commercial Portfolio Segment [Member] | Peoples Commercial [Member]
Acquired impaired loans evaluated for impairment	0	4,371
Allowance for acquired impaired loans	0	0
Commercial Portfolio Segment [Member] | 1-4 family, Senior-commercial [Member]
Acquired impaired loans evaluated for impairment	0	4,564
Allowance for acquired impaired loans	0	0
Commercial Portfolio Segment [Member] | Construction and Land Development [Member]
Acquired impaired loans evaluated for impairment	958	1,956
Allowance for acquired impaired loans	0	0
Commercial Portfolio Segment [Member] | Farmland and Other Agricultural [Member]
Acquired impaired loans evaluated for impairment	2,242	3,722
Allowance for acquired impaired loans	0	0
Commercial Portfolio Segment [Member] | Multifamily [Member]
Acquired impaired loans evaluated for impairment	1,614	1,663
Allowance for acquired impaired loans	0	0
Commercial Portfolio Segment [Member] | Commercial Real Estate-owner Occupied [Member]
Acquired impaired loans evaluated for impairment	16,717	13,024
Allowance for acquired impaired loans	0	0
Commercial Portfolio Segment [Member] | Commercial Real Estate Non-owner Occupied [Member]
Acquired impaired loans evaluated for impairment	3,459	8,686
Allowance for acquired impaired loans	0	0
Commercial Portfolio Segment [Member] | Commercial and Industrial [Member]
Acquired impaired loans evaluated for impairment	814	2,829
Allowance for acquired impaired loans	0	0
Commercial Portfolio Segment [Member] | Other Commercial Loan [Member]
Acquired impaired loans evaluated for impairment	0	352
Allowance for acquired impaired loans	0	0
Consumer Real Estate Portfolio Segment [Member]
Acquired impaired loans evaluated for impairment	13,858	20,080
Allowance for acquired impaired loans	0	0
Consumer Real Estate Portfolio Segment [Member] | Waccamaw Serviced Home Equity Lines [Member]
Acquired impaired loans evaluated for impairment	0	2,121
Allowance for acquired impaired loans	0	0
Consumer Real Estate Portfolio Segment [Member] | Waccamaw Residential [Member]
Acquired impaired loans evaluated for impairment	0	587
Allowance for acquired impaired loans	0	0
Consumer Real Estate Portfolio Segment [Member] | 1-4 Family, Junior and HELOCS [Member]
Acquired impaired loans evaluated for impairment	761	2,157
Allowance for acquired impaired loans	0	0
Consumer Real Estate Portfolio Segment [Member] | 1-4 Family, Senior-consumer [Member]
Acquired impaired loans evaluated for impairment	12,494	13,174
Allowance for acquired impaired loans	0	0
Consumer Real Estate Portfolio Segment [Member] | Consumer Loan [Member]
Acquired impaired loans evaluated for impairment	603	1,341
Allowance for acquired impaired loans	0	0
Consumer Real Estate Portfolio Segment [Member] | Peoples Residential [Member]
Acquired impaired loans evaluated for impairment	0	700
Allowance for acquired impaired loans	$ 0	$ 0