Note 7 - Loans - Troubled Debt Restructuring (Details)	3 Months Ended		6 Months Ended
	Jun. 30, 2017 USD ($)	Jun. 30, 2016 USD ($)	Jun. 30, 2017 USD ($)	Jun. 30, 2016 USD ($)
No. of Contracts	1	6	3	6
Pre-Modification Outstanding Recorded Investment	$ 500,000	$ 5,211,000	$ 28,183,000	$ 5,211,000
Post-Modification Outstanding Recorded Investment	500,000	5,211,000	28,183,000	5,211,000
Charge-offs
Special Reserve		$ 171,000		$ 171,000
Commercial Portfolio Segment [Member]
No. of Contracts	1	4	1	4
Pre-Modification Outstanding Recorded Investment	$ 500,000	$ 4,844,000	$ 500,000	$ 4,844,000
Post-Modification Outstanding Recorded Investment	500,000	4,844,000	500,000	4,844,000
Charge-offs			2,100,000
Special Reserve		$ 148,000		$ 148,000
Residential Mortgage and Equity Lines Portfolio Segment [Member]
No. of Contracts		2		2
Pre-Modification Outstanding Recorded Investment		$ 367,000		$ 367,000
Post-Modification Outstanding Recorded Investment		367,000		367,000
Charge-offs
Special Reserve		$ 23,000		$ 23,000
Real Estate Construction Portfolio Segment [Member]
No. of Contracts			2
Pre-Modification Outstanding Recorded Investment			$ 27,683,000
Post-Modification Outstanding Recorded Investment			27,683,000
Charge-offs
Special Reserve