Note 7 - Stock-based Compensation (Detail) - Common stock options outstanding (USD $)					12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009	Dec. 31, 2012 Exercise Price 1 [Member] 2007 Incentive Plan [Member]	Dec. 31, 2012 Exercise Price 2 [Member] 2007 Incentive Plan [Member]	Dec. 31, 2012 Exercise Price 3 [Member] 2007 Incentive Plan [Member]	Dec. 31, 2012 Exercise Price 4 [Member] 2007 Incentive Plan [Member]
Number of Options Outstanding	1,316,068	1,002,350	1,004,750	1,476,491	921,500	25,000	10,000	359,568
Exercise Price Per Share (in Dollars per share)	$ 5.98	$ 7.50	$ 7.51	$ 8.28	$ 7.64	$ 3.61	$ 2.10	$ 1.99
Remaining Contractual Life					36 days	146 days	219 days	8 years 109 days
Number of Options Outstanding That Are Exercisable	956,500				921,500	25,000	10,000
Exercise Price per Share of Options That Are Exercisable (in Dollars per share)					$ 7.64	$ 3.61	$ 2.10