Long-Term Debt - Summary of long term debt (Details) - USD ($)	Sep. 30, 2020	Dec. 31, 2019
Debt Instrument
Long-term debt	$ 10,139,000	$ 6,019,000
Less current portion	(849,000)	(849,000)
Long-term debt, Noncurrent	9,290,000	5,170,000
Paycheck Protection Program Loan [Member]
Debt Instrument
Long-term debt	4,000,000	0
Line of credit payable to a financial institution; Interest rate option of bank prime or Libor plus 1.65% (B)
Debt Instrument
Long-term debt	3,750,000	3,000,000
Term loan payable to a financial institution; Interest rate option of bank prime or Libor plus 1.4% (1.556% as of September30, 2020), monthly principal payments of $21,833 through 2021 with a balloon payment of $786,000 due December 1, 2021(C).
Debt Instrument
Long-term debt	1,114,000	1,310,000
Term loan payable to a financial institution; Interest rate option of bank prime or Libor plus 1.4% (1.556% as of September 30, 2020), monthly principal payments of $23,810 through December 1, 2021(C).
Debt Instrument
Long-term debt	357,000	571,000
Equipment note obligations; Interest rate fixed for term of each funding based upon the Lender's lease pricing at time of funding. (Interest rate/factor 1.8259% - 1.835015% as of June 30, 2020)(D)
Debt Instrument
Long-term debt	569,000	670,000
Equipment financing lease obligations; Interest rate fixed for term of each funding based upon the Lender's lease pricing at time of funding. (Interest rate/factor 1.822758% - 1.869304% at time of funding)(E)
Debt Instrument
Long-term debt	$ 349,000	$ 468,000

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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 of long-term debt and lease obligation, classified as current.

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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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