Note 11 - Stock-Based Compensation (Detail) (USD $)	9 Months Ended		12 Months Ended	9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Dec. 31, 2011	Sep. 30, 2012 Directors [Member]	Sep. 30, 2012 Employee Stock Purchase Plan [Member]	Sep. 30, 2012 Restricted Stock [Member]	Sep. 30, 2012 Stock Options [Member]	Sep. 30, 2012 Restricted Stock [Member]	Sep. 30, 2012 2005 Plan [Member]	May 31, 2005 2005 Plan [Member]	Sep. 30, 2012 2010 Plan [Member]	May 31, 2010 2010 Plan [Member]
Incentive Stock Option Term	10
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized										1,200,000		1,200,000
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant									115,620		469,904
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross	64,244		1,264,719	45,000	19,144
Share-based Compensation (in Dollars)	$ 1,925,000	$ 2,253,000
Employee Service Share-based Compensation, Nonvested Awards, Total Compensation Cost Not yet Recognized (in Dollars)	$ 6,545,000						$ 6,007,000	$ 538,000
Employee Service Share-based Compensation, Nonvested Awards, Total Compensation Cost Not yet Recognized, Period for Recognition						1 year 219 days	3 years 146 days