Long-Term Debt (Details) - Long-term debt - USD ($)	3 Months Ended	12 Months Ended
Mar. 31, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
Long-term debt, including current portion	$ 2,985,000	$ 2,222,000
Less portion due within one year	2,335,000	1,572,000
Net long-term debt	650,000	650,000
Total debt	3,199,000	2,222,000
Less deferred financing costs	214,000
8¼% Limited Convertible Senior Subordinated Notes Due 2012 [Member]
Debt Instrument [Line Items]
Long-term debt, including current portion	352,000	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	977,000
Term Loan [Member]
Debt Instrument [Line Items]
Long-term debt, including current portion	1,000,000	1,000,000
Forgivable Loan [Member]
Debt Instrument [Line Items]
Long-term debt, including current portion	$ 650,000	$ 650,000

Total debt before deduction of deferred financing costs.

No definition available.

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- Definition

Amount of amortization expense attributable to debt issuance costs.

+ References

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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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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Amount after unamortized (discount) premium and debt issuance costs of long-term debt classified as noncurrent and excluding amounts to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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