Note 2 - Securities (Details) - Available-for-sale Securities - USD ($)		Sep. 30, 2015	Dec. 31, 2014
Schedule of Available-for-sale Securities [Line Items]
Securities available for sale, amortized cost		$ 365,456,000	$ 432,591,000
Securities available for sale, gross unrealized gains		4,060,000	3,897,000
Securities available for sale, gross unrealized losses		(2,343,000)	(3,576,000)
Securities available for sale	[1]	367,173,000	432,912,000
US Government Agencies Debt Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Securities available for sale, amortized cost		159,411,000	194,894,000
Securities available for sale, gross unrealized gains		1,939,000	1,612,000
Securities available for sale, gross unrealized losses		(1,957,000)	(3,038,000)
Securities available for sale		159,393,000	193,468,000
Collateralized Mortgage Backed Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Securities available for sale, amortized cost		72,211,000	92,656,000
Securities available for sale, gross unrealized gains		904,000	1,123,000
Securities available for sale, gross unrealized losses		(151,000)	(218,000)
Securities available for sale		72,964,000	93,561,000
Municipal General Obligation Bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Securities available for sale, amortized cost		122,724,000	132,347,000
Securities available for sale, gross unrealized gains		1,118,000	1,042,000
Securities available for sale, gross unrealized losses		(234,000)	(307,000)
Securities available for sale		123,608,000	133,082,000
Municipal Revenue Bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Securities available for sale, amortized cost		9,163,000	10,769,000
Securities available for sale, gross unrealized gains		88,000	117,000
Securities available for sale, gross unrealized losses		(1,000)	(13,000)
Securities available for sale		9,250,000	10,873,000
Other Debt Obligations [Member]
Schedule of Available-for-sale Securities [Line Items]
Securities available for sale, amortized cost		1,947,000	1,925,000
Securities available for sale, gross unrealized gains		11,000	3,000
Securities available for sale, gross unrealized losses		0	0
Securities available for sale		$ 1,958,000	$ 1,928,000

[1] See Note 11 for a description of the fair value hierarchy as well as a disclosure of levels for classes of financial assets and liabilities.