Note 7 - Loans and Allowance for Loan Losses - Allowance for Loan Losses and the Recorded Investment in Loans by Impairment Method (Details) - USD ($)	Sep. 30, 2016	Jun. 30, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Dec. 31, 2014
Real Estate Portfolio Segment [Member]
Individually evaluated for impairment	$ 2,265,000		$ 2,515,000
Collectively evaluated for impairment	5,657,000		6,658,000
Total ending allowance balance	7,922,000	$ 8,404,000	9,173,000	$ 9,928,000	$ 10,806,000	$ 12,542,000
Loans individually evaluated for impairment	42,838,000		36,625,000
Loans collectively evaluated for impairment	806,749,000		820,411,000
Loans, net of unearned income	849,587,000		857,036,000
Commercial Portfolio Segment [Member]
Individually evaluated for impairment	209,000		223,000
Collectively evaluated for impairment	718,000		597,000
Total ending allowance balance	927,000	806,000	820,000	1,024,000	1,057,000	1,153,000
Loans individually evaluated for impairment	409,000		400,000
Loans collectively evaluated for impairment	90,885,000		89,420,000
Loans, net of unearned income	91,294,000		89,820,000
Consumer Portfolio Segment [Member]
Individually evaluated for impairment	147,000		156,000
Collectively evaluated for impairment	150,000		166,000
Total ending allowance balance	297,000	275,000	322,000	325,000	336,000	273,000
Loans individually evaluated for impairment	148,000		157,000
Loans collectively evaluated for impairment	9,687,000		12,262,000
Loans, net of unearned income	9,835,000		12,419,000
Individually evaluated for impairment	2,621,000		2,894,000
Collectively evaluated for impairment	6,525,000		7,421,000
Total ending allowance balance	9,146,000	$ 9,485,000	10,315,000	$ 11,277,000	$ 12,199,000	$ 13,968,000
Loans individually evaluated for impairment	43,395,000		37,182,000
Loans collectively evaluated for impairment	907,321,000		922,093,000
Loans, net of unearned income	$ 950,716,000		$ 959,275,000