Note 14 - Financial Derivatives (Details Textual) - USD ($)	1 Months Ended	3 Months Ended		6 Months Ended
	May 31, 2014	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015	Dec. 31, 2015
Interest Rate Swap [Member] | Cash Flow Hedging [Member] | Designated as Hedging Instrument [Member] | Interest Expense [Member]
Net Accrued on Interest Rate Swaps		$ 593,000	$ 703,000	$ 1,200,000	$ 1,400,000
Interest Rate Swap [Member] | Cash Flow Hedging [Member] | Designated as Hedging Instrument [Member]
Derivative Outstanding, Notional Amount	$ 119,100,000
Derivative Original Maturity	10 years
Derivative, Average Fixed Interest Rate	2.61%
Derivative, Average Variable Interest Rate	0.65%
Derivative, Notional Amount		119,100,000		119,100,000
Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, Net of Tax		(7,400,000)
Interest Rate Swap [Member] | Fair Value Hedging [Member] | Designated as Hedging Instrument [Member] | Interest Expense [Member]
Net Accrued on Interest Rate Swaps		$ 946,000	682,000	1,900,000	1,400,000
Interest Rate Swap [Member] | Fair Value Hedging [Member] | Designated as Hedging Instrument [Member] | Minimum [Member]
Derivative Original Maturity		4 years
Interest Rate Swap [Member] | Fair Value Hedging [Member] | Designated as Hedging Instrument [Member] | Maximum [Member]
Derivative Original Maturity		8 years
Interest Rate Swap [Member] | Fair Value Hedging [Member] | Designated as Hedging Instrument [Member]
Derivative Outstanding, Notional Amount		$ 360,500,000		$ 360,500,000
Derivative, Average Fixed Interest Rate		4.65%		4.65%
Derivative, Average Variable Interest Rate		3.65%		3.65%
Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, Net of Tax		$ (5,300,000)
Derivative, Average Basis Spread on Variable Rate		3.19%		3.19%
Positive Fair Value [Member]
Sum Of Spot And Forward Contract Notional Amount		$ 85,100,000		$ 85,100,000		$ 100,600,000
Positive Fair Value		2,100,000		2,100,000		3,300,000
Negative Fair Value [Member]
Sum Of Spot And Forward Contract Notional Amount		84,400,000		84,400,000		115,400,000
Notional Amount Of Option Contract						9,400,000
Negative Fair Value		1,600,000		1,600,000		4,100,000
Open OptionContracts Fair Value						$ 28,000
Cash [Member]
Collateral Already Posted, Aggregate Fair Value		16,300,000		16,300,000
Junior Subordinated Notes	$ 119,100,000
Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, Net of Tax		(1,282,000)	$ 2,328,000	(4,402,000)	$ 740,000
Notional Amount Of Option Contract		$ 0		$ 0