Note 9 - Securities Sold Under Agreements to Repurchase (Details) - Contractual Maturity of the Agreements - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Repurchase agreements:
U.S. Government agencies	$ 96,800	$ 100,800
US Government Agencies Debt Securities [Member]
Repurchase agreements:
U.S. Government agencies	96,838	100,771
Maturity Overnight [Member] | US Government Agencies Debt Securities [Member]
Repurchase agreements:
U.S. Government agencies	89,512	93,454
Maturity Less than 30 Days [Member] | US Government Agencies Debt Securities [Member]
Repurchase agreements:
U.S. Government agencies	0	0
Maturity 30 to 90 Days [Member] | US Government Agencies Debt Securities [Member]
Repurchase agreements:
U.S. Government agencies	0	0
Maturity Greater than 90 Days [Member] | US Government Agencies Debt Securities [Member]
Repurchase agreements:
U.S. Government agencies	$ 7,326	$ 7,317