Note 13 - Employee Benefit Plans (Details) - USD ($)	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Note 13 - Employee Benefit Plans (Details) [Line Items]
Employee Stock Ownership Plan (ESOP), Compensation Expense	$ 5,230,000	$ 3,659,000	$ 3,076,000
Deferred Compensation Arrangement with Individual, Compensation Expense	804,000	453,000	473,000
Allocated Share-based Compensation Expense	4,018,000	$ 1,366,000	$ 1,417,000
Employee Service Share-based Compensation, Nonvested Awards, Compensation Not yet Recognized, Stock Options	1,442,000
Employee Service Share-based Compensation, Nonvested Awards, Compensation Not yet Recognized, Share-based Awards Other than Options	$ 5,300,000
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition	3 years 109 days
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Intrinsic Value	$ 5,219,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Intrinsic Value	$ 3,448,000
Share Price (in Dollars per share)	$ 51.36
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period (in Shares)	71,368	64,720	24,290
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Intrinsic Value	$ 2,054,000	$ 957,000	$ 298,000
Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price (in Dollars per share)	$ 7.81
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross (in Shares)	375,000	0	0
Employee Stock Purchase Plan 2011 [Member]
Note 13 - Employee Benefit Plans (Details) [Line Items]
Defined Contribution Plan, Maximum Annual Contributions Per Employee, Percent	3.00%
Defined Contribution Plan, Maximum Annual Contributions Per Employee, Amount	$ 7,500
Defined Contribution Plan, Requisite Service Period	2 years
Share-based Compensation Arrangement by Share-based Payment Award, Purchase Price of Common Stock, Percent	95.00%
Special Employee Stock Purchase Plan 2015 [Member]
Note 13 - Employee Benefit Plans (Details) [Line Items]
Defined Contribution Plan, Maximum Annual Contributions Per Employee, Amount	$ 25,000
Defined Contribution Plan, Requisite Service Period	2 years
Share-based Compensation Arrangement by Share-based Payment Award, Purchase Price of Common Stock, Percent	85.00%
Retirement Plan 401k [Member]
Note 13 - Employee Benefit Plans (Details) [Line Items]
Defined Contribution Plan, Cost Recognized	$ 1,048,000	$ 837,000	$ 690,000