Note 8 - Changes in Accumulated Other Comprehensive Income (Loss) By Component (1) (Details) - Accumulated Other Comprehensive Loss - USD ($) $ in Thousands		3 Months Ended			12 Months Ended
		Mar. 31, 2016		Mar. 31, 2015	Dec. 31, 2015
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance	[1]	$ (3,165)		$ (632)	$ (632)
Balance		(1,195)	[1]	(189)	(3,165)	[1]
Unrealized loss on securities	[1]	2,122		404	(2,577)
Amounts reclassified from accumulated other comprehensive income to net income	[1],[2]	(152)		39	44
Net current-period other comprehensive income (loss)	[1]	1,970		443	(2,533)
Accumulated Net Investment Gain (Loss) Attributable to Parent [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance	[1]	(2,562)		82	82
Balance		(629)	[1]	488	(2,562)	[1]
Unrealized loss on securities	[1]	2,122		404	(2,577)
Amounts reclassified from accumulated other comprehensive income to net income	[1],[2]	(189)		2	(67)
Net current-period other comprehensive income (loss)	[1]	1,933		406	(2,644)
Accumulated Net Investment Gain (Loss) on Securities Transferred from Available-for-Sale to Held-to-Maturity [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance	[1]	(603)		(714)	(714)
Balance		$ (566)	[1]	$ (677)	$ (603)	[1]
Unrealized loss on securities	[1]
Amounts reclassified from accumulated other comprehensive income to net income	[1],[2]	$ 37		$ 37	$ 111
Net current-period other comprehensive income (loss)	[1]	$ 37		$ 37	$ 111

[1] All amounts are net of tax. Amounts in parentheses indicate reductions to other comprehensive income.

[2] Reclassification amounts are reported as gains on sales of investment securities, impairment losses, and amortization of net unrealizedlosses on the Consolidated Statement of Operations.