Note 2 - Securities (Details) - Securities in a Continuous Loss Position - USD ($)	Mar. 31, 2016	Dec. 31, 2015
Note 2 - Securities (Details) - Securities in a Continuous Loss Position [Line Items]
Securities available for sale, continuous unrealized loss position, less than 12 months	$ 18,042,000	$ 21,452,000
Securities available for sale, continuous unrealized loss position, less than 12 months, unrealized loss	172,000	78,000
Securities available for sale, continuous unrealized loss position, 12 months or more	70,328,000	142,424,000
Securities available for sale, continuous unrealized loss position, 12 months or more, unrealized loss	667,000	1,991,000
Securities available for sale, continuous unrealized loss position	88,370,000	163,876,000
Securities available for sale, continuous unrealized loss position, unrealized loss	839,000	2,069,000
US Government Agencies Debt Securities [Member]
Note 2 - Securities (Details) - Securities in a Continuous Loss Position [Line Items]
Securities available for sale, continuous unrealized loss position, less than 12 months	7,046,000	0
Securities available for sale, continuous unrealized loss position, less than 12 months, unrealized loss	114,000	0
Securities available for sale, continuous unrealized loss position, 12 months or more	42,601,000	76,496,000
Securities available for sale, continuous unrealized loss position, 12 months or more, unrealized loss	466,000	1,552,000
Securities available for sale, continuous unrealized loss position	49,647,000	76,496,000
Securities available for sale, continuous unrealized loss position, unrealized loss	580,000	1,552,000
Collateralized Mortgage Backed Securities [Member]
Note 2 - Securities (Details) - Securities in a Continuous Loss Position [Line Items]
Securities available for sale, continuous unrealized loss position, less than 12 months	7,942,000	18,025,000
Securities available for sale, continuous unrealized loss position, less than 12 months, unrealized loss	36,000	69,000
Securities available for sale, continuous unrealized loss position, 12 months or more	17,055,000	34,660,000
Securities available for sale, continuous unrealized loss position, 12 months or more, unrealized loss	75,000	235,000
Securities available for sale, continuous unrealized loss position	24,997,000	52,685,000
Securities available for sale, continuous unrealized loss position, unrealized loss	111,000	304,000
Municipal General Obligation Bonds [Member]
Note 2 - Securities (Details) - Securities in a Continuous Loss Position [Line Items]
Securities available for sale, continuous unrealized loss position, less than 12 months	3,054,000	1,981,000
Securities available for sale, continuous unrealized loss position, less than 12 months, unrealized loss	22,000	4,000
Securities available for sale, continuous unrealized loss position, 12 months or more	10,551,000	30,134,000
Securities available for sale, continuous unrealized loss position, 12 months or more, unrealized loss	126,000	201,000
Securities available for sale, continuous unrealized loss position	13,605,000	32,115,000
Securities available for sale, continuous unrealized loss position, unrealized loss	148,000	205,000
Municipal Revenue Bonds [Member]
Note 2 - Securities (Details) - Securities in a Continuous Loss Position [Line Items]
Securities available for sale, continuous unrealized loss position, less than 12 months	0	0
Securities available for sale, continuous unrealized loss position, less than 12 months, unrealized loss	0	0
Securities available for sale, continuous unrealized loss position, 12 months or more	121,000	1,134,000
Securities available for sale, continuous unrealized loss position, 12 months or more, unrealized loss	1,000	3,000
Securities available for sale, continuous unrealized loss position	121,000	1,134,000
Securities available for sale, continuous unrealized loss position, unrealized loss	1,000	3,000
Other Debt Obligations [Member]
Note 2 - Securities (Details) - Securities in a Continuous Loss Position [Line Items]
Securities available for sale, continuous unrealized loss position, less than 12 months	0	1,446,000
Securities available for sale, continuous unrealized loss position, less than 12 months, unrealized loss	0	5,000
Securities available for sale, continuous unrealized loss position, 12 months or more	0	0
Securities available for sale, continuous unrealized loss position, 12 months or more, unrealized loss	0	0
Securities available for sale, continuous unrealized loss position	0	1,446,000
Securities available for sale, continuous unrealized loss position, unrealized loss	$ 0	$ 5,000