Note 6 - Stockholders Equity and Equity Compensation (Detail) (USD $)	3 Months Ended	12 Months Ended		24 Months Ended			3 Months Ended						3 Months Ended	12 Months Ended	3 Months Ended
	Mar. 31, 2012	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2012	Mar. 31, 2012 Employee Plan [Member]	Mar. 31, 2012 Director Plan [Member]	Mar. 31, 2012 Restricted Stock [Member]	Mar. 31, 2011 Restricted Stock [Member]	Mar. 31, 2012 Stock Options [Member]	Mar. 31, 2011 Stock Options [Member]	Mar. 31, 2012 Minimum [Member]	Mar. 31, 2012 Maximum [Member]	Mar. 31, 2012 In Connection with Equity Compensation Programs [Member]	Dec. 31, 2012 In Connection with Equity Compensation Programs [Member]	Mar. 31, 2012 Through the Open Market Repurchase Program [Member]
Stock Repurchase Program, Authorized Amount		$ 5,000,000	$ 5,000,000	$ 10,000,000										$ 5,000,000
Stock Repurchased During Period, Shares (in Shares)													56,991		310,035
Stock Repurchased During Period, Value	6,037,000												1,000,000		5,000,000
Treasury Stock Acquired, Average Cost Per Share (in Dollars per share)													$ 18.12		$ 16.13
Number of Equity-Based Compensation Plans	2
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized (in Shares)					2,500,000	200,000
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant (in Shares)					800,000	200,000
Vesting Goals, Measurement Term	3
Allocated Share-based Compensation Expense							1,000,000	1,100,000	600,000	700,000
Employee Service Share-based Compensation, Nonvested Awards, Total Compensation Cost Not yet Recognized							$ 10,500,000		$ 3,700,000
Employee Service Share-based Compensation, Nonvested Awards, Total Compensation Cost Not yet Recognized, Period for Recognition							2 years 6 months		2 years 4 months
Deferred Stock Unit, Share Transfer Obligation (in Shares)	1
Stock Options, General Term											7	10
Price Per Share For Intrinsic Value Calculation Stock Options (in Dollars per share)									$ 17.83	$ 26.75