Stock And Stock Options (Narrative) (Details)					12 Months Ended
	Feb. 25, 2021	Mar. 17, 2017 $ / shares	Mar. 21, 2016	Feb. 01, 2008 shares	Dec. 31, 2020 $ / shares	Oct. 25, 2020 shares	Dec. 31, 2019 $ / shares	Mar. 16, 2017 $ / shares
Stock Options [Line Items]
Number of shares that may be granted | shares						7,000,000
Number of additional shares that may be granted | shares				3,500,000
Stock incentive plan term					10 years
Purchase price floor of fair market value					85.00%
Common stock, par value | $ / shares		$ 0.001			$ 0.001		$ 0.001
Reverse stock split			0.1
Voluntary Resignation [Member]
Stock Options [Line Items]
Stock Incentive Plan exercisable period					3 months
Subsequent Event [Member]
Stock Options [Line Items]
Reverse stock split	0.083
Series A Preferred Stock [Member]
Stock Options [Line Items]
Exercise price | $ / shares								$ 1.10
Rights Plan [Member]
Stock Options [Line Items]
Common stock, Threshold for exercise of rights percentage		4.95%