Note 4 - Investments - Available-for-Sale Marketable Securities (Details) (USD $)	3 Months Ended	12 Months Ended
	Mar. 31, 2015	Dec. 31, 2014
Available-for-sale Securities, Current	$ 2,307,000	$ 2,840,000	[1]
Marketable Securities [Member]
Cost basis	327,000	327,000
Gains previously recognized on warrants	380,000	380,000
Gains included in accumulated other comprehensive income	1,600,000	2,133,000
Available-for-sale Securities, Current	$ 2,307,000	$ 2,840,000

[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.