Note 5 - Deposits (Details) - Summary of Deposits - USD ($)	9 Months Ended
	Sep. 30, 2015	Dec. 31, 2014
Summary of Deposits [Abstract]
Noninterest-bearing checking (in Dollars)	$ 619,125,000	$ 558,738,000
Noninterest-bearing checking	27.50%	24.50%
Noninterest-bearing checking	10.80%
Interest-bearing checking (in Dollars)	$ 389,978,000	$ 413,382,000
Interest-bearing checking	17.30%	18.20%
Interest-bearing checking	(5.70%)
Money market (in Dollars)	$ 283,707,000	$ 235,587,000
Money market	12.60%	10.30%
Money market	20.40%
Savings (in Dollars)	$ 342,902,000	$ 330,459,000
Savings	15.20%	14.50%
Savings	3.80%
Time, under $100,000 (in Dollars)	$ 162,729,000	$ 181,026,000
Time, under $100,000	7.20%	8.00%
Time, under $100,000	(10.10%)
Time, $100,000 and over (in Dollars)	$ 333,226,000	$ 382,120,000
Time, $100,000 and over	14.80%	16.80%
Time, $100,000 and over	(12.80%)
(in Dollars)	$ 2,131,667,000	$ 2,101,312,000
	94.60%	92.30%
	1.40%
Out-of-area time, under $100,000 (in Dollars)	$ 298,000	$ 2,422,000
Out-of-area time, under $100,000	0.10%	0.10%
Out-of-area time, under $100,000	(87.70%)
Out-of-area time, $100,000 and over (in Dollars)	$ 122,164,000	$ 173,181,000
Out-of-area time, $100,000 and over	5.40%	7.60%
Out-of-area time, $100,000 and over	(29.50%)
(in Dollars)	$ 122,462,000	$ 175,603,000
	5.40%	7.70%
	(30.20%)
Total deposits (in Dollars)	$ 2,254,129,000	$ 2,276,915,000
Total deposits	100.00%	100.00%
Total deposits	(1.00%)