Note 10 - Shareholders Equity (Detail) (USD $)	0 Months Ended	12 Months Ended				0 Months Ended	12 Months Ended				1 Months Ended				1 Months Ended		1 Months Ended	12 Months Ended									0 Months Ended
	Mar. 02, 2012	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009	Mar. 02, 2012 Warrant, Period to Purchase, Years [Member]	Dec. 31, 2012 Issued in 2008 [Member]	Dec. 31, 2008 Issued in 2008 [Member]	Dec. 31, 2012 Issued in 2009 [Member]	Dec. 31, 2009 Issued in 2009 [Member]	Dec. 31, 2009 Woodstone [Member] Minimum [Member]	Dec. 31, 2012 Woodstone [Member]	Dec. 31, 2009 Woodstone [Member]	Dec. 31, 2009 Woodstone $10 Million Contract [Member]	Dec. 31, 2009 Warrants Exercisable to Woodstone, 400,000 Shares [Member]	Dec. 31, 2009 Woodstone $5 Million Contract [Member]	Dec. 31, 2009 Warrants Exercisable to Woodstone, 200,000 Share [Member]	Dec. 31, 2012 Director [Member]	Dec. 31, 2012 Stock Options Plans [Member] Minimum [Member]	Dec. 31, 2012 Stock Options Plans [Member] Maximum [Member]	Dec. 31, 2012 2008 Incentive Stock Plan [Member]	Dec. 31, 2012 1994 Employee Stock Purchase Plan [Member]	Dec. 31, 2011 1994 Employee Stock Purchase Plan [Member]	Dec. 31, 2010 1994 Employee Stock Purchase Plan [Member]	Dec. 31, 2012 Minimum [Member]	Dec. 31, 2012 Maximum [Member]	Mar. 02, 2012 Number of Investors [Member]	Mar. 02, 2012 Number of New Investors [Member]	Mar. 02, 2012 Largest Single Investment [Member]	Mar. 02, 2012 Included in One Unit [Member]
Proceeds from Issuance or Sale of Equity (in Dollars)	$ 4,900,000																												$ 1,000,000
Sale of Stock, Description of Transaction																											ten	Eight
Partners' Capital Account, Units, Sold in Private Placement	19,600,000
Common Stock, Shares, Issued		44,698,650	24,913,135																											1
Common Stock, Par or Stated Value Per Share (in Dollars per share)		$ 0.0001	$ 0.0001																											$ 0.0001
Class of Warrant or Right, Outstanding		13,056,378	3,256,378	3,291,378	4,437,639
Class of Warrant or Right, Number of Securities Called by Warrants or Rights			(160,000)	(1,730,062)									600,000	400,000		200,000														1
Sale of Equity, Unit Price	$0.25
Class of Warrant or Right, Exercise Price of Warrants or Rights (in Dollars per Item)		0.76	1.43	1.42	1.24							0.49																		0.54
Class of Warrant or Rights, Description						three
Class of Warrant or Right, Original Price (in Dollars per share)								$ 3.08		$ 0.65
Class of Warrant or Right, Re-priced (in Dollars per share)							$ 1.97		$ 0.49
Related Party Transaction, Amounts of Transaction (in Dollars)											15,000,000	4,400,000			10,000,000		5,000,000
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized																					5,000,000	600,000
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant																					3,300,000
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Date																					Dec. 31, 2008
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period																		1 year	1 year	4 years					3 years	4 years
Employee Service Share-based Compensation, Nonvested Awards, Total Compensation Cost Not yet Recognized (in Dollars)		$ 228,000	$ 373,000
Employee Service Share-based Compensation, Nonvested Awards, Total Compensation Cost Not yet Recognized, Period for Recognition		1 year	1 year 109 days
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value (in Dollars per share)		$ 0.15	$ 0.47	$ 0.80
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Remaining Contractual Term		10 years
Share-based Compensation Arrangement by Share-based Payment Award, Purchase Price of Common Stock, Percent																						85.00%
Share-based Compensation Arrangement by Share-based Payment Award, Shares Issued in Period																						476,000	291,000	134,000