Long-Term Debt (Details) - Long-Term Debt - USD ($)	3 Months Ended	12 Months Ended
Mar. 31, 2021	Dec. 31, 2020
Debt Instrument [Line Items]
Long-term debt, including current portion	$ 2,887,000	$ 2,815,000
Less portion due within one year	2,618,000	2,546,000
Net long-term debt	269,000	269,000
Total debt	3,035,000	2,995,000
Less deferred financing costsand debt discount	148,000	180,000
8¼% Limited Convertible Senior Subordinated Notes Due 2012 [Member]
Debt Instrument [Line Items]
Long-term debt, including current portion	302,000	352,000
9½% Subordinated Debentures Due 2012 [Member]
Debt Instrument [Line Items]
Long-term debt, including current portion	220,000	220,000
Revolving Credit Line [Member]
Debt Instrument [Line Items]
Long-term debt, including current portion	702,000	612,000
Related Party Term Loan [Member]
Debt Instrument [Line Items]
Long-term debt, including current portion	1,000,000	1,000,000
Term Loan [Member]
Debt Instrument [Line Items]
Long-term debt, including current portion	$ 811,000	$ 811,000

Total debt before deduction of deferred financing costs.

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Amount of amortization expense attributable to debt issuance costs.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt, classified as current. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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