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Liquidity (Narrative) (Details) - USD ($)					12 Months Ended
Liquidity (Narrative) (Details) - USD ($)	Jan. 26, 2021	Mar. 27, 2020	Feb. 12, 2020	Jan. 27, 2020	Dec. 31, 2020	Dec. 31, 2019
Cash and cash equivalents					$ 9,649,000	$ 6,033,000
Liquidity, management evaluation					The Company has prepared its consolidated financial statements on a going concern basis, which assumes that the Company will realize its assets and satisfy its liabilities in the normal course of business. However, the Company has incurred net losses since its inception and has negative operating cash flows. These circumstances raise substantial doubt about the Company's ability to continue as a going concern. The accompanying financial statements do not include any adjustments to reflect the possible future effects on the recoverability and classification of assets or the amounts and classifications of liabilities that may result from the outcome of the uncertainty concerning the Company's ability to continue as a going concern.
Common stock, par value (in dollars per share)					$ 0.01	$ 0.01
Securities Purchase Agreement [Member]
Proceeds from issuance of private placement		$ 25,000,000
Securities Purchase Agreement [Member] \| Common Stock Subject to Mandatory Redemption [Member]
Shares Issued, Price Per Share		$ 2.87		$ 2.87
Stock Issued During Period, Shares, New Issues		8,710,800		8,710,800
Securities Purchase Agreement [Member] \| Common Stock Subject to Mandatory Redemption [Member] \| Subsequent Event [Member]
Shares Issued, Price Per Share	$ 3.25
Stock Issued During Period, Shares, New Issues	6,153,847
Common stock, par value (in dollars per share)	$ 0.01
Securities Purchase Agreement [Member] \| Warrants and Rights Subject to Mandatory Redemption [Member]
Class of Warrant or Right, Number of Securities Called by Warrants or Rights		8,710,800		8,710,800
Securities Purchase Agreement [Member] \| Warrants and Rights Subject to Mandatory Redemption [Member] \| Subsequent Event [Member]
Class of Warrant or Right, Number of Securities Called by Warrants or Rights	6,153,847
Securities Purchase Agreement First Tranche [Member]
Stock Issued During Period, Shares, New Issues			993,139
Proceeds from issuance of private placement			$ 2,800,000
Securities Purchase Agreement First Tranche [Member] \| Subsequent Event [Member]
Class of Warrant or Right, Number of Securities Called by Warrants or Rights	1,867,912
Proceeds from issuance of private placement	$ 6,100,000
Securities Purchase Agreement First Tranche [Member] \| Common Stock Subject to Mandatory Redemption [Member] \| Subsequent Event [Member]
Stock Issued During Period, Shares, New Issues	1,867,912
Securities Purchase Agreement Second Tranche [Member]
Stock Issued During Period, Shares, New Issues		7,717,661
Proceeds from issuance of private placement		$ 22,200,000
Securities Purchase Agreement Second Tranche [Member] \| Subsequent Event [Member]
Shares Issued, Price Per Share	$ 13.90
Securities Purchase Agreement Second Tranche [Member] \| Common Stock Subject to Mandatory Redemption [Member] \| Subsequent Event [Member]
Stock Issued During Period, Shares, New Issues	4,285,935
Securities Purchase Agreement Second Tranche [Member] \| Warrants and Rights Subject to Mandatory Redemption [Member] \| Subsequent Event [Member]
Class of Warrant or Right, Number of Securities Called by Warrants or Rights	4,285,935