Note 7 - Income Taxes (Details Textual) - USD ($)	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Domestic Tax Authority [Member] | Internal Revenue Service (IRS) [Member] | Earliest Tax Year [Member]
Open Tax Year	2012
Domestic Tax Authority [Member] | Internal Revenue Service (IRS) [Member] | Latest Tax Year [Member]
Open Tax Year	2015
Domestic Tax Authority [Member] | Internal Revenue Service (IRS) [Member]
Operating Loss Carryforwards	$ 242,900,000
State and Local Jurisdiction [Member] | California Franchise Tax Board [Member] | Earliest Tax Year [Member]
Open Tax Year	2011
State and Local Jurisdiction [Member] | California Franchise Tax Board [Member] | Latest Tax Year [Member]
Open Tax Year	2015
State and Local Jurisdiction [Member] | California Franchise Tax Board [Member]
Operating Loss Carryforwards	$ 149,000,000
Deferred Tax Assets, Net	0
Unrecognized Tax Benefits that Would Impact Effective Tax Rate	0
Valuation Allowance, Deferred Tax Asset, Increase (Decrease), Amount	8,566,000	$ 6,667,000
Unrecognized Tax Benefits	$ 2,800,000