Long-Term Debt - Summary (Details) - USD ($)	3 Months Ended	12 Months Ended
Mar. 31, 2021	Dec. 31, 2020
Debt Instrument [Line Items]
Long-term debt	$ 62,987,000	$ 64,876,000
Less: unamortized loan fees	(98,000)	(102,000)
Less: current portion	(11,841,000)	(11,364,000)
Long-term debt, net of current portion	51,048,000	53,410,000
Promissory Note
Debt Instrument [Line Items]
Maximum borrowing capacity	5,000,000
Amount converted to term loan	4,814,677
Term Loan, Maturing March 2023
Debt Instrument [Line Items]
Long-term debt	2,078,000	2,322,000
Monthly principal and interest payments	$ 90,815
Fixed interest rate	4.98%
Equipment Loan, Draw Down Period Ending August 28, 2019
Debt Instrument [Line Items]
Maximum borrowing capacity	$ 10,000,000
Amount converted to term loan	9,476,000
Term Loan, Maturing July 2024
Debt Instrument [Line Items]
Long-term debt	6,977,000	7,450,000
Monthly principal and interest payments	$ 192,572
Fixed interest rate	5.75%
Term Loan, Maturing April 30, 2021
Debt Instrument [Line Items]
Long-term debt	$ 53,000	$ 212,000
Monthly principal and interest payments	$ 53,539
Fixed interest rate	3.25%	3.25%
Face amount of loan	$ 2,130,000
Term Loan, Maturing December 31, 2021
Debt Instrument [Line Items]
Long-term debt	176,000	$ 234,000
Monthly principal and interest payments	$ 19,834
Fixed interest rate	3.50%
Face amount of loan	$ 935,000
Subtotal 1
Debt Instrument [Line Items]
Long-term debt	9,284,000	$ 10,218,000
Equipment Loan With Draw Down Period Ending May 31, 2019 [Member]
Debt Instrument [Line Items]
Maximum borrowing capacity	$ 10,000,000
Fixed interest rate	3.25%	3.25%
Term Loan, Maturing May 31, 2024
Debt Instrument [Line Items]
Long-term debt	$ 6,500,000	$ 7,000,000
Term Loan, Maturing December 2024
Debt Instrument [Line Items]
Long-term debt	2,301,000	$ 2,444,000
Monthly principal and interest payments	$ 57,769
Fixed interest rate	3.50%
Face amount of loan	$ 3,000,000
Term Loan, Maturing December 2024 \| Prime Rate
Debt Instrument [Line Items]
Variable rate basis	prime rate plus 0.25%
Basis spread on variable rate	0.25%
Interest rate during the period	3.50%	3.50%
Term Loan, Maturing May 2029
Debt Instrument [Line Items]
Long-term debt	$ 21,052,000	$ 21,130,000
Face amount of loan	21,580,000
Debt issuance costs	119,000
Term Loan, Maturing May 2029 \| Minimum
Debt Instrument [Line Items]
Monthly principal and interest payments	24,356
Term Loan, Maturing May 2029 \| Maximum
Debt Instrument [Line Items]
Monthly principal and interest payments	$ 39,581
Term Loan, Maturing May 2029 \| Prime Rate
Debt Instrument [Line Items]
Variable rate basis	prime rate less 0.25%
Basis spread on variable rate	0.25%
Interest rate during the period	3.00%	3.00%
Term Loan, Maturing June 17, 2025
Debt Instrument [Line Items]
Long-term debt	$ 2,583,000	$ 2,723,000
Monthly principal and interest payments	54,623
Face amount of loan	3,000,000
Term Loan, Maturing June 17, 2025 \| Minimum
Debt Instrument [Line Items]
Monthly principal and interest payments	30,524
Term Loan, Maturing June 17, 2025 \| Maximum
Debt Instrument [Line Items]
Monthly principal and interest payments	$ 37,720
Term Loan, Maturing June 17, 2025 \| Prime Rate
Debt Instrument [Line Items]
Variable rate basis	prime rate plus margin of 0.25%
Basis spread on variable rate	0.25%
Interest rate during the period	3.50%	3.50%
Paycheck Protection Program Loan
Debt Instrument [Line Items]
Long-term debt	$ 5,000,000	$ 5,000,000
Fixed interest rate	1.00%
Face amount of loan	$ 5,000,000
Subtotal 2
Debt Instrument [Line Items]
Long-term debt	46,720,000	48,515,000
Term Loan, Maturing June 30, 2025
Debt Instrument [Line Items]
Long-term debt	$ 16,267,000	$ 16,361,000
Fixed interest rate	4.50%
Face amount of loan	$ 16,540,000

This amount represent the amount converted to term loan

No definition available.

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Maximum borrowing capacity under the terms of the debt instrument without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding.

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Amount after unamortized (discount) premium and debt issuance costs of long-term debt classified as noncurrent and excluding long term line of credit.

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Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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The reference rate for the variable rate of the debt instrument, such as LIBOR or the US Treasury rate and the maturity of the reference rate used, such as three months or six months LIBOR.

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Face (par) amount of debt instrument at time of issuance.

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The average effective interest rate during the reporting period.

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Contractual interest rate for funds borrowed, under the debt agreement.

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Amount of the required periodic payments including both interest and principal payments.

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Amount, before accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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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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