Long-Term Debt - Schedule of Long-term Debt (Details) - USD ($)	9 Months Ended	12 Months Ended
Sep. 30, 2021	Dec. 31, 2020
Debt Instrument [Line Items]
Long-term debt	$ 37,005,000	$ 64,876,000
Less: unamortized loan fees	(210,000)	(102,000)
Long-term debt, current portion	(1,166,000)	(11,364,000)
Long-term debt, net of current portion and debt discount of $0.2 million and $0.1 million at September 30, 2021 and December 31, 2020, respectively (including $35.6 million and $36.7 million associated with variable interest entity at September 30, 2021 and December 31, 2020, respectively, and debt discount of $0.2 million and $0.1 million associated with variable interest entity at September 30, 2021 and December 31, 2020, respectively)	35,629,000	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	0	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	0	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	$ 0	$ 212,000
Monthly principal and interest payments	55,539
Fixed interest rate		3.25%
Face amount of loan	2,130,000
Term Loan, Maturing December 31, 2021
Debt Instrument [Line Items]
Long-term debt	0	$ 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	0	$ 10,218,000
Equipment Loan With Draw Down Period Ending May 31, 2019
Debt Instrument [Line Items]
Maximum borrowing capacity	10,000,000
Fixed interest rate		3.25%
Term Loan, Maturing May 31, 2024
Debt Instrument [Line Items]
Long-term debt	0	$ 7,000,000
Term Loan, Maturing December 2024
Debt Instrument [Line Items]
Long-term debt	0	$ 2,444,000
Monthly principal and interest payments	57,769
Face amount of loan	$ 3,000,000
Term Loan, Maturing December 2024 \| Prime Rate
Debt Instrument [Line Items]
Basis spread on variable rate	0.25%
Interest rate during the period		3.50%
Term Loan, Maturing May 2029
Debt Instrument [Line Items]
Long-term debt	$ 20,890,000	$ 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]
Basis spread on variable rate	0.25%
Interest rate during the period		3.00%
Term Loan, Maturing June 17, 2025
Debt Instrument [Line Items]
Long-term debt	$ 0	$ 2,723,000
Monthly principal and interest payments	54,623
Face amount of loan	$ 3,000,000
Term Loan, Maturing June 17, 2025 \| Prime Rate
Debt Instrument [Line Items]
Basis spread on variable rate	0.25%
Interest rate during the period		3.50%
Paycheck Protection Program, CARES Act
Debt Instrument [Line Items]
Long-term debt	$ 0	$ 5,000,000
Fixed interest rate	1.00%
Face amount of loan	$ 5,000,000
Subtotal 2
Debt Instrument [Line Items]
Long-term debt	20,890,000	48,515,000
Term Loan, Maturing June 30, 2025
Debt Instrument [Line Items]
Long-term debt	$ 0	16,361,000
Fixed interest rate	4.50%
Face amount of loan	$ 16,540,000
Term Loan, Maturing June 30, 2025 \| Minimum
Debt Instrument [Line Items]
Monthly principal and interest payments	30,524
Term Loan, Maturing June 30, 2025 \| Maximum
Debt Instrument [Line Items]
Monthly principal and interest payments	37,720
Term Loan, Maturing September 30, 2026
Debt Instrument [Line Items]
Long-term debt	16,115,000	$ 0
Amount converted to term loan	16,115,000
Monthly principal and interest payments	$ 115,766
Fixed interest rate	3.50%
Face amount of loan	$ 23,000,000
Term loan, accordion feature	$ 6,885,000

This amount represent the amount converted to term loan

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

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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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