Note 11 - Share-Based Payments (Details) - Stock-Based Compensation Expense (USD $)	3 Months Ended				6 Months Ended				12 Months Ended
	Jun. 30, 2013		Jun. 30, 2012		Jun. 30, 2013		Jun. 30, 2012		Dec. 31, 2012
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Compensation Expense									$ 23,000
Benefit for income taxes (1)		[1]		[1]		[1]		[1]
Net compensation expense	41,000		159,000		88,000		404,000
General and Administrative Expense [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Compensation Expense	30,000		130,000		66,000		317,000
Other Research and Development Expense [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Compensation Expense	11,000		29,000		22,000		87,000
Stock-based Compensation Expense [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Compensation Expense	$ 41,000		$ 159,000		$ 88,000		$ 404,000

[1] The stock-based compensation expense has not been tax-effected due to the recording of a full valuation allowance against net deferred tax assets.