Note 11 - Fair Value of Financial Instruments and Fair Value Measurements - Quantitative Information for Financial Instruments Measured at Fair Value (Details) - Fair Value, Inputs, Level 3 [Member] - Fair Value, Measurements, Nonrecurring [Member] - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2017	Dec. 31, 2016
Commercial Portfolio Segment [Member] | Market Approach Valuation Technique [Member] | Commercial Construction [Member]
Assets measured at fair value	$ 51
Real Estate Portfolio Segment [Member] | Market Approach Valuation Technique [Member] | Commercial Construction [Member]
Assets measured at fair value		$ 51
Real Estate Portfolio Segment [Member] | Market Approach Valuation Technique [Member] | Commercial Construction [Member] | Minimum [Member]
Fair value inputs, comparability adjustments	(5.00%)	(5.00%)
Fair value inputs, management adjustments	0.00%	0.00%
Real Estate Portfolio Segment [Member] | Market Approach Valuation Technique [Member] | Commercial Construction [Member] | Maximum [Member]
Fair value inputs, comparability adjustments	99.00%	99.00%
Fair value inputs, management adjustments	10.00%	10.00%
Real Estate Portfolio Segment [Member] | Market Approach Valuation Technique [Member] | Commercial Construction [Member] | Weighted Average [Member]
Fair value inputs, comparability adjustments	47.00%	47.00%
Fair value inputs, management adjustments	5.00%	5.00%
Real Estate Portfolio Segment [Member] | Market Approach Valuation Technique [Member] | Residential [Member]
Assets measured at fair value	$ 417	$ 1,105
Real Estate Portfolio Segment [Member] | Market Approach Valuation Technique [Member] | Residential [Member] | Minimum [Member]
Fair value inputs, comparability adjustments	(22.00%)	(22.00%)
Fair value inputs, management adjustments	0.00%	0.00%
Real Estate Portfolio Segment [Member] | Market Approach Valuation Technique [Member] | Residential [Member] | Maximum [Member]
Fair value inputs, comparability adjustments	0.00%	0.00%
Fair value inputs, management adjustments	40.00%	40.00%
Real Estate Portfolio Segment [Member] | Market Approach Valuation Technique [Member] | Residential [Member] | Weighted Average [Member]
Fair value inputs, comparability adjustments	(11.00%)	(11.00%)
Fair value inputs, management adjustments	20.00%	20.00%
Real Estate Portfolio Segment [Member] | Market Approach Valuation Technique [Member] | Commercial [Member]
Assets measured at fair value	$ 1,455	$ 5,445
Real Estate Portfolio Segment [Member] | Market Approach Valuation Technique [Member] | Commercial [Member] | Minimum [Member]
Fair value inputs, comparability adjustments		(14.08%)
Fair value inputs, management adjustments	0.00%	0.00%
Real Estate Portfolio Segment [Member] | Market Approach Valuation Technique [Member] | Commercial [Member] | Maximum [Member]
Fair value inputs, comparability adjustments		24.62%
Fair value inputs, management adjustments	100.00%	100.00%
Real Estate Portfolio Segment [Member] | Market Approach Valuation Technique [Member] | Commercial [Member] | Weighted Average [Member]
Fair value inputs, comparability adjustments		5.27%
Fair value inputs, management adjustments	50.00%	50.00%
Real Estate Portfolio Segment [Member] | Market Approach Valuation Technique [Member] | Farmland [Member]
Assets measured at fair value	$ 351	$ 351
Real Estate Portfolio Segment [Member] | Market Approach Valuation Technique [Member] | Farmland [Member] | Minimum [Member]
Fair value inputs, comparability adjustments	(27.00%)	(27.00%)
Fair value inputs, management adjustments	10.00%	10.00%
Real Estate Portfolio Segment [Member] | Market Approach Valuation Technique [Member] | Farmland [Member] | Maximum [Member]
Fair value inputs, comparability adjustments	15.00%	15.00%
Fair value inputs, management adjustments	75.00%	75.00%
Real Estate Portfolio Segment [Member] | Market Approach Valuation Technique [Member] | Farmland [Member] | Weighted Average [Member]
Fair value inputs, comparability adjustments	(6.00%)	(6.00%)
Fair value inputs, management adjustments	42.50%	42.50%
Real Estate Portfolio Segment [Member] | Market Approach Valuation Technique [Member] | Other Real Estate Owned [Member]
Assets measured at fair value	$ 2,231	$ 2,505
Real Estate Portfolio Segment [Member] | Market Approach Valuation Technique [Member] | Other Real Estate Owned [Member] | Minimum [Member]
Fair value inputs, comparability adjustments	(50.80%)	(50.80%)
Fair value inputs, management adjustments	6.25%	6.25%
Real Estate Portfolio Segment [Member] | Market Approach Valuation Technique [Member] | Other Real Estate Owned [Member] | Maximum [Member]
Fair value inputs, comparability adjustments	302.00%	316.00%
Fair value inputs, management adjustments	81.26%	76.92%
Real Estate Portfolio Segment [Member] | Market Approach Valuation Technique [Member] | Other Real Estate Owned [Member] | Weighted Average [Member]
Fair value inputs, comparability adjustments	125.60%	132.60%
Fair value inputs, management adjustments	33.47%	36.31%
Real Estate Portfolio Segment [Member] | Income Approach Valuation Technique [Member] | Commercial [Member] | Weighted Average [Member]
Fair value inputs, management adjustments		10.67%
Fair value inputs, capitalization rate	10.00%
Real Estate Portfolio Segment [Member] | Income Approach Valuation Technique [Member] | Other Real Estate Owned [Member] | Weighted Average [Member]
Range Weighted Average	12.50%	12.50%