Note 3 - Stock Based Compensation (Details) (USD $) In Millions, except Share data, unless otherwise specified	3 Months Ended	6 Months Ended	3 Months Ended	6 Months Ended	0 Months Ended			6 Months Ended
	Jun. 30, 2014 2014 and 2003 Stock Option Plan [Member]	Jun. 30, 2014 2014 and 2003 Stock Option Plan [Member]	Jun. 30, 2013 2003 Stock Option Plan [Member]	Jun. 30, 2013 2003 Stock Option Plan [Member]	May 02, 2013 Restricted Stock [Member] Director [Member]	May 04, 2013 Restricted Stock [Member] Director [Member]	May 02, 2013 Restricted Stock [Member] Management [Member]	Jun. 30, 2014 Restricted Stock [Member]	May 02, 2014 2014 Plan [Member]
Note 3 - Stock Based Compensation (Details) [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized									7,500,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period	182,000	238,000	93,000	270,000
Proceeds from Stock Options Exercised (in Dollars)	$ 1.1	$ 1.3	$ 0.4	$ 0.7
Employee Service Share-based Compensation, Tax Benefit from Compensation Expense (in Dollars)	$ 3.9	$ 5.0	$ 1.0	$ 3.1
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period					71,582	31,899		72,000
Deferred Compensation Arrangement With Individual Common Stock Vested Immediately Upon Issuance						15,946
Deferred Compensation Arrangement with Individual, Common Stock Reserved for Future Issuance						15,953
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage							25.00%