Note 1 - Organization and Summary of Significant Accounting Policies (Details) (USD $)	12 Months Ended		129 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2013
Note 1 - Organization and Summary of Significant Accounting Policies (Details) [Line Items]
Number of Operating Segments	2
Marketable Securities	$ 331,000		$ 331,000
Marketable Securities, Unrealized Gain (Loss)	20,000
Inventory Valuation Reserves	102,000	78,000	102,000
Operating Leases, Income Statement, Lease Revenue	1,566,000	2,231,000
Operating Leases, Future Minimum Payments Receivable	125,000	120,000	125,000
Cost-method Investments, Other than Temporary Impairment		17,000
Equity Method Investments	914,000	892,000	914,000
Cost Method Investments	736,000	667,000	736,000
Finite-Lived Intangible Asset, Useful Life	10 years
Product Warranty Accrual	141,000	164,000	141,000
Allocated Share-based Compensation Expense	82,000	79,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross (in Shares)	17,000	17,000	1,215,500
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value (in Dollars per share)	$ 1.05	$ 1.28
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized	49,000		49,000
General and Administrative Expense [Member]
Note 1 - Organization and Summary of Significant Accounting Policies (Details) [Line Items]
Depreciation	386,000	476,000
The 2011 Non-employee Directors Stock Option Plan [Member]
Note 1 - Organization and Summary of Significant Accounting Policies (Details) [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross (in Shares)	17,000	17,000
Previously Written-off [Member]
Note 1 - Organization and Summary of Significant Accounting Policies (Details) [Line Items]
Gain on Sale of Investments	1,000
Patents [Member]
Note 1 - Organization and Summary of Significant Accounting Policies (Details) [Line Items]
Amortization of Intangible Assets	$ 49,000