Note 7 - Loans and Allowance for Loan Losses - Allowance for Loan Losses and the Recorded Investment In Loans by Impairment Method (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Jun. 30, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Dec. 31, 2015
Individually evaluated for impairment	$ 2,788		$ 2,948
Collectively evaluated for impairment	6,260		6,396
Total ending allowance balance	9,048	$ 9,222	9,344	$ 9,146	$ 9,485	$ 10,315
Loans individually evaluated for impairment	34,529		41,895
Loans collectively evaluated for impairment	960,582		929,080
Loans, net of unearned income	995,111		970,975
Real Estate Portfolio Segment [Member]
Individually evaluated for impairment	2,348		2,566
Collectively evaluated for impairment	5,480		5,639
Total ending allowance balance	7,828	7,961	8,205	7,922	8,404	9,173
Loans individually evaluated for impairment	33,815		41,311
Loans collectively evaluated for impairment	848,115		829,581
Loans, net of unearned income	881,930		870,892
Commercial Portfolio Segment [Member]
Individually evaluated for impairment	219		236
Collectively evaluated for impairment	664		618
Total ending allowance balance	883	900	854	927	806	820
Loans individually evaluated for impairment	401		438
Loans collectively evaluated for impairment	104,010		90,410
Loans, net of unearned income	104,411		90,848
Consumer Portfolio Segment [Member]
Individually evaluated for impairment	221		146
Collectively evaluated for impairment	116		139
Total ending allowance balance	337	$ 361	285	$ 297	$ 275	$ 322
Loans individually evaluated for impairment	313		146
Loans collectively evaluated for impairment	8,457		9,089
Loans, net of unearned income	$ 8,770		$ 9,235