Note 7 - Segment Reporting (Details) - USD ($)	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Dec. 31, 2015
Operating Segments [Member] | DPC [Member]
Revenues	$ 948,000	$ 924,000
Intersegment revenues	6,000	111,000
Total Revenues by Major Customer	954,000	1,035,000
Depreciation and amortization expense	19,000	18,000
Operating income (loss)	$ (214,000)	$ (265,000)
Impairment of investment
Other income, net
Net loss	$ (221,000)	$ (265,000)
Expenditures for segment assets	23,000	46,000
Total assets	2,182,000	$ 2,799,000
Tax expense
Operating Segments [Member] | DPL [Member]
Revenues	$ 765,000	$ 972,000
Intersegment revenues
Total Revenues by Major Customer	$ 765,000	$ 972,000
Depreciation and amortization expense	21,000	40,000
Operating income (loss)	$ 14,000	$ 46,000
Impairment of investment
Other income, net
Net loss	$ 28,000	$ 61,000
Expenditures for segment assets	49,000	53,000
Total assets	$ 2,745,000	$ 3,249,000
Tax expense
Intersegment Eliminations [Member]
Revenues
Intersegment revenues	$ (6,000)	$ (111,000)
Total Revenues by Major Customer	$ (6,000)	$ (111,000)
Depreciation and amortization expense
Operating income (loss)
Impairment of investment
Other income, net
Net loss
Expenditures for segment assets
Total assets
Tax expense
Revenues	$ 1,713,000	$ 1,896,000
Intersegment revenues
Total Revenues by Major Customer	$ 1,713,000	$ 1,896,000
Depreciation and amortization expense	40,000	58,000
Operating income (loss)	$ (200,000)	(219,000)
Impairment of investment		(50,000)
Other income, net	$ 7,000	65,000
Net loss	(193,000)	(204,000)
Expenditures for segment assets	72,000	99,000
Total assets	$ 4,927,000	$ 6,048,000	$ 5,099,000
Tax expense