Long-Term Debt - Summary of long term debt (Details) - USD ($)	Mar. 31, 2021	Dec. 31, 2020
Debt Instrument
Long-term debt	$ 10,090,000	$ 9,928,000
Less current portion	(2,575,000)	(2,635,000)
Long-term debt, Noncurrent	7,515,000	7,293,000
Paycheck protection program payable to financial institutions: Interest rate of 1% per annum. Unforgiven portion is payable monthly until April 20, 2022 (A)
Debt Instrument
Long-term debt	4,000,000	4,000,000
Line of credit payable to a financial institution; Interest rate option of bank prime or Libor plus 2.15000% (B)(C)
Debt Instrument
Long-term debt	4,250,000	3,750,000
Term loan payable to a financial institution; Interest rate option of bank prime or Libor plus 1.515130%, monthly principal payments of $21,833 through 2021 with a balloon payment of $286,000 due December 1, 2021(C).
Debt Instrument
Long-term debt	483,000	1,048,000
Term loan payable to a financial institution; Interest rate option of bank prime or Libor plus 1.515130%, monthly principal payments of $23,810 through December 1, 2021(C).
Debt Instrument
Long-term debt	214,000	286,000
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 1.7955% - 1.8350% as of March 31, 2021)(D)
Debt Instrument
Long-term debt	872,000	534,000
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 1.8227% - 1.8690% at time of funding)(E)
Debt Instrument
Long-term debt	$ 271,000	$ 310,000

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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.

+ References

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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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