Note 4 - Investments - Investment in Common Stock Warrants (Details) - USD ($)		6 Months Ended
		Jun. 30, 2015	Jun. 30, 2014
Warrant [Member]
Beginning balance			$ 350,000
Gain on investment in common stock warrants			30,000
Fair value of warrants exercised			$ (380,000)
Ending balance
Beginning balance	[1]	$ 2,840,000
Gain on investment in common stock warrants			$ (30,000)
Ending balance		$ 1,495,000

[1] The condensed consolidated balance sheet as of December 31, 2014 has been prepared using information from the audited consolidated balance sheet as of that date.