Note 7 - Investment Securities (Details) - Credit-Related Other-Than-Temporary Impairment - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Credit-Related Other-Than-Temporary Impairment [Abstract]
Balance, beginning of period			$ 1,153,000	$ 1,271,000
Reductions: gain on payoff			0	0
Additions:
Initial credit impairments			0	0
Subsequent credit impairments	$ 0	$ 0	0	0
Balance, end of period	$ 1,153,000	$ 1,271,000	$ 1,153,000	$ 1,271,000