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Stock And Stock Options (Narrative) (Details) |  |  |  | 12 Months Ended |  |
--- | --- | --- | --- | --- | --- | ---
Mar. 17, 2017 $ / shares | Mar. 21, 2016 | Feb. 01, 2008 shares | Dec. 31, 2019 USD ($) item $ / shares shares | Dec. 31, 2018 USD ($) item $ / shares shares | Mar. 16, 2017 $ / shares | Oct. 25, 2000 shares
Stock Options [Line Items] |  |  |  |  |  |  |
Number of shares that may be granted |  |  |  |  |  |  | 7,000,000
Number of additional shares that may be granted |  |  | 3,500,000 |  |  |  |
Stock Incentive Plan term |  |  |  | 10 years |  |  |
Purchase price floor of fair market value |  |  |  | 85.00% |  |  |
Stock based compensation | $ |  |  |  | $ 17,000 | $ 23,000 |  |
Reverse stock split |  | 0.1 |  |  |  |  |
Common stock, shares issued |  |  |  | 10,658,775 | 10,639,290 |  |
Common stock, par value | $ / shares |  |  |  | $ 0.001 | $ 0.001 |  |
Directors And CEO [Member] |  |  |  |  |  |  |
Stock Options [Line Items] |  |  |  |  |  |  |
Stock based compensation | $ |  |  |  | $ 17,000 |  |  |
Common stock, shares issued |  |  |  | 19,485 | 19,366 |  |
Three Non-Executive Directors [Member] |  |  |  |  |  |  |
Stock Options [Line Items] |  |  |  |  |  |  |
Number of additional shares that may be granted |  |  |  | 0 | 0 |  |
Number of directors | item |  |  |  | 3 | 3 |  |
Voluntary Resignation [Member] |  |  |  |  |  |  |
Stock Options [Line Items] |  |  |  |  |  |  |
Stock Incentive Plan exercisable period |  |  |  | 3 months |  |  |
Rights Agreement [Member] |  |  |  |  |  |  |
Stock Options [Line Items] |  |  |  |  |  |  |
Date declared |  |  |  | Mar. 17, 2017 |  |  |
Date to be paid |  |  |  | Mar. 27, 2017 |  |  |
Date of record |  |  |  | Mar. 16, 2017 |  |  |
Common stock, Threshold for exercise of rights percentage | 4.95% |  |  |  |  |  |
Rights Agreement [Member] | Series A Preferred Stock [Member] |  |  |  |  |  |  |
Stock Options [Line Items] |  |  |  |  |  |  |
Common stock, par value | $ / shares | $ 0.001 |  |  |  |  |  |
Exercise price | $ / shares |  |  |  |  |  | $ 1.10 |
Dividends conversion ratio |  |  |  | 1.000 |  |  |
Rights Agreement [Member] | Right [Member] |  |  |  |  |  |  |
Stock Options [Line Items] |  |  |  |  |  |  |
Number of preferred share purchase right for each outstanding share of its common stock to shareholder | $ / shares | $ 1 |  |  |  |  |  |

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