Note 1 - Nature of Business and Significant Accounting Policies (Details) - Option Pricing Model Valuation Assumptions (USD $)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Note 1 - Nature of Business and Significant Accounting Policies (Details) - Option Pricing Model Valuation Assumptions [Line Items]
Expected life of option grants (years)		10 years
Weighted-average grant date fair value (in Dollars per share)	$ 5.14	$ 2.79	$ 2.74
Employee Stock Option [Member]
Note 1 - Nature of Business and Significant Accounting Policies (Details) - Option Pricing Model Valuation Assumptions [Line Items]
Dividend yield		0.86%
Expected volatility		29.36%
Risk-free interest rate		1.98%
Expected life of option grants (years)	6 years	6 years	6 years
Weighted-average grant date fair value (in Dollars per share)	$ 5.14	$ 2.79	$ 2.74
Employee Stock Option [Member] | Minimum [Member]
Note 1 - Nature of Business and Significant Accounting Policies (Details) - Option Pricing Model Valuation Assumptions [Line Items]
Dividend yield	0.44%		0.88%
Expected volatility	29.50%		29.64%
Risk-free interest rate	1.71%		1.90%
Employee Stock Option [Member] | Maximum [Member]
Note 1 - Nature of Business and Significant Accounting Policies (Details) - Option Pricing Model Valuation Assumptions [Line Items]
Dividend yield	0.53%		1.00%
Expected volatility	30.56%		30.30%
Risk-free interest rate	2.90%		3.58%
Stock Purchase Grants [Member]
Note 1 - Nature of Business and Significant Accounting Policies (Details) - Option Pricing Model Valuation Assumptions [Line Items]
Dividend yield
Expected volatility
Risk-free interest rate
Expected life of option grants (years)
Weighted-average grant date fair value (in Dollars per share)	$ 2.10	$ 1.71	$ 1.68
Stock Purchase Grants [Member] | Minimum [Member]
Note 1 - Nature of Business and Significant Accounting Policies (Details) - Option Pricing Model Valuation Assumptions [Line Items]
Dividend yield	0.53%	0.61%	0.88%
Expected volatility	23.05%	27.20%	51.62%
Risk-free interest rate	0.10%	0.03%	0.08%
Expected life of option grants (years)	3 years	3 years	3 years
Stock Purchase Grants [Member] | Maximum [Member]
Note 1 - Nature of Business and Significant Accounting Policies (Details) - Option Pricing Model Valuation Assumptions [Line Items]
Dividend yield	0.61%	0.88%	1.12%
Expected volatility	24.25%	31.11%	53.58%
Risk-free interest rate	0.18%	0.18%	0.23%
Expected life of option grants (years)	6 years	6 years	6 years