Note 9 - Supplemental Information Relating to Oil and Gas Producing Activities (Unaudited) - Estimated Quantities of Proved Oil and Gas Reserves (Details)	12 Months Ended
	Dec. 31, 2016 bbl Mcf	Dec. 31, 2015 bbl Mcf	Dec. 31, 2014 bbl Mcf
Oil [Member]
Beginning Balance | bbl	277,000	511,000
Extensions, discoveries and other additions | bbl	5,000	2,000
Production | bbl	(34,000)	(44,000)
Revision of previous estimates | bbl	(4,000)	(192,000)
Ending Balance | bbl	244,000	277,000
PROVED DEVELOPED RESERVES:
Proved developed reserves | bbl	244,000	277,000	511,000
Natural Gas [Member]
Beginning Balance | Mcf	7,991,000	23,724,000
Extensions, discoveries and other additions | Mcf	13,000	5,000
Production | Mcf	(1,157,000)	(1,616,000)
Revision of previous estimates | Mcf	(1,567,000)	(14,122,000)
Ending Balance | Mcf	5,280,000	7,991,000
PROVED DEVELOPED RESERVES:
Proved developed reserves | Mcf	5,280,000	7,991,000	23,724,000