Note 6 - Stockholders' Equity and Equity Compensation (Details) (USD $) In Millions, except Share data, unless otherwise specified	1 Months Ended			3 Months Ended	9 Months Ended		12 Months Ended			9 Months Ended				3 Months Ended		9 Months Ended		3 Months Ended		9 Months Ended
	Sep. 30, 2013	May 31, 2013	Dec. 31, 2012	Sep. 30, 2013	Sep. 30, 2013	Sep. 30, 2012	Dec. 31, 2013	Sep. 30, 2013 Minimum [Member]	Sep. 30, 2013 Maximum [Member]	Sep. 30, 2013 Through the Open Market Repurchase Program [Member]	Sep. 30, 2013 In Connection with Equity Compensation Programs [Member]	Sep. 30, 2013 Employee Plan [Member]	Sep. 30, 2013 Director Plan [Member]	Sep. 30, 2013 Deferred Stock Units [Member]	Sep. 30, 2012 Deferred Stock Units [Member]	Sep. 30, 2013 Deferred Stock Units [Member]	Sep. 30, 2012 Deferred Stock Units [Member]	Sep. 30, 2013 Employee Stock Option [Member]	Sep. 30, 2012 Employee Stock Option [Member]	Sep. 30, 2013 Employee Stock Option [Member]	Sep. 30, 2012 Employee Stock Option [Member]
Note 6 - Stockholders' Equity and Equity Compensation (Details) [Line Items]
Stock Repurchase Program, Authorized Amount	$ 10.0	$ 10.0	$ 5.0				$ 10.0
Stock Repurchased During Period, Shares (in Shares)										782,260	51,292
Stock Repurchased During Period, Value										17.8	1.2
Treasury Stock Acquired, Average Cost Per Share (in Dollars per share)										$ 22.79	$ 23.32
Number of Equity-Based Compensation Plans	3			3	3
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized (in Shares)												2,895,000	250,000
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant (in Shares)												2,840,257	168,390
Allocated Share-based Compensation Expense				0.8	2.8	3.0								0	0	0.9	0.7	0.4	0.5	1.4	1.6
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized	$ 10.1			$ 10.1	$ 10.1													$ 1.5		$ 1.5
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition					2 years 1 month 6 days															1 year 6 months
Deferred Stock Unit, Share Transfer Obligation (in Shares)	1			1	1
Stock Options, General Term								7 years	10 years
Price Per Share For Intrinsic Value Calculation Stock Options (in Dollars per share)	$ 23.72			$ 23.72	$ 23.72	$ 19.16