Note 17 - Regulatory Matters (Details) - Risk Based Capital Amounts and Ratios - USD ($) $ in Thousands		Sep. 30, 2015	Dec. 31, 2014
Total risk-based capital (1)
Total risk-based capital, actual amount	[1]	$ 298,667	$ 280,228
Total risk-based capital, actual ratio	[1]	13.68%	13.86%
Total risk-based capital, minimum for adequately capitalized amount	[1]	$ 174,659	$ 161,748
Total risk-based capital, minimum for adequately capitalized ratio	[1]	8.00%	8.00%
Total risk-based capital, minimum for well capitalized amount	[1]
Total risk-based capital, minimum for well capitalized ratio	[1]
Common Equity Tier 1 risk-based capital (2)
Common Equity Tier 1 risk-based capital, actual amount	[2]	$ 276,681
Common Equity Tier 1 risk-based capital, actual ratio	[2]	12.68%
Common Equity Tier 1 risk-based capital, minimum for adequately capitalized amount	[2]	$ 98,191
Common Equity Tier 1 risk-based capital, minimum for adequately capitalized ratio	[2]	4.50%
Common Equity Tier 1 risk-based capital, minimum for well capitalized amount	[2]
Common Equity Tier 1 risk-based capital, minimum for well capitalized ratio	[2]
Tier 1 risk-based capital (1)
Tier 1 risk-based capital, actual amount	[1]	$ 276,681	$ 255,308
Tier 1 risk-based capital, actual ratio	[1]	12.68%	12.63%
Tier 1 risk-based capital, minimum for adequately capitalized amount	[1]	$ 130,922	$ 80,858
Tier 1 risk-based capital, minimum for adequately capitalized ratio	[1]	6.00%	4.00%
Tier 1 risk-based capital, minimum for well capitalized amount	[1]
Tier 1 risk-based capital, minimum for well capitalized ratio	[1]
Leverage (3)
Leverage, actual amount	[3]	$ 276,681	$ 255,308
Leverage, actual ratio	[3]	10.82%	10.26%
Leverage, minimum for adequately capitalized amount	[3]	$ 102,285	$ 74,651
Leverage, minimum for adequately capitalized ratio	[3]	4.00%	3.00%
Leverage, minimum for well capitalized amount	[3]
Leverage, minimum for well capitalized ratio	[3]
Subsidiaries [Member]
Total risk-based capital (1)
Total risk-based capital, actual amount	[1]	$ 290,863	$ 274,345
Total risk-based capital, actual ratio	[1]	13.35%	13.59%
Total risk-based capital, minimum for adequately capitalized amount	[1]	$ 174,300	$ 161,498
Total risk-based capital, minimum for adequately capitalized ratio	[1]	8.00%	8.00%
Total risk-based capital, minimum for well capitalized amount	[1]	$ 217,875	$ 201,873
Total risk-based capital, minimum for well capitalized ratio	[1]	10.00%	10.00%
Common Equity Tier 1 risk-based capital (2)
Common Equity Tier 1 risk-based capital, actual amount	[2]	$ 268,877
Common Equity Tier 1 risk-based capital, actual ratio	[2]	12.34%
Common Equity Tier 1 risk-based capital, minimum for adequately capitalized amount	[2]	$ 98,051
Common Equity Tier 1 risk-based capital, minimum for adequately capitalized ratio	[2]	4.50%
Common Equity Tier 1 risk-based capital, minimum for well capitalized amount	[2]	$ 130,734
Common Equity Tier 1 risk-based capital, minimum for well capitalized ratio	[2]	6.00%
Tier 1 risk-based capital (1)
Tier 1 risk-based capital, actual amount	[1]	$ 268,877	$ 249,425
Tier 1 risk-based capital, actual ratio	[1]	12.34%	12.36%
Tier 1 risk-based capital, minimum for adequately capitalized amount	[1]	$ 130,734	$ 80,720
Tier 1 risk-based capital, minimum for adequately capitalized ratio	[1]	6.00%	4.00%
Tier 1 risk-based capital, minimum for well capitalized amount	[1]	$ 130,734	$ 121,080
Tier 1 risk-based capital, minimum for well capitalized ratio	[1]	6.00%	6.00%
Leverage (3)
Leverage, actual amount	[3]	$ 268,877	$ 249,425
Leverage, actual ratio	[3]	10.52%	10.04%
Leverage, minimum for adequately capitalized amount	[3]	$ 102,235	$ 74,529
Leverage, minimum for adequately capitalized ratio	[3]	4.00%	3.00%
Leverage, minimum for well capitalized amount	[3]	$ 127,793	$ 124,216
Leverage, minimum for well capitalized ratio	[3]	5.00%	5.00%

[1] Ratio is computed in relation to risk-weighted assets.

[2] Ratio became effective January 2015.

[3] Ratio is computed in relation to average assets.