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

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Represents the accrued interest amount of Paycheck Protection Program loan forgiveness.

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Represents the principle amount of loan on Paycheck Protection Program loan forgiveness.

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Represents the percentage of PPP loan proceeds used to pay for payroll costs.

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

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

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

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Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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

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The fee, expressed as a percentage of the line of credit facility, for available but unused credit capacity under the credit facility.

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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 payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of long-term debt payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing in fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of long-term debt payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing in fourth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of long-term debt payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing in third fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Period between issuance and maturity of long-term debt, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Amount of cash inflow from contractual arrangement with the lender, including but not limited to, letter of credit, standby letter of credit and revolving credit arrangements.

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Long-Term Debt - Additional Information (Details) - USD ($)		3 Months Ended	9 Months Ended
	Apr. 21, 2020	Sep. 30, 2021	Sep. 30, 2021	Sep. 30, 2020	Jul. 09, 2021	Apr. 21, 2021	Dec. 31, 2020	Jun. 28, 2018
Debt Instrument
Gain on Paycheck Protection Program loan forgiveness		$ 4,000,000	$ 4,000,000
Amount drawn			500,000	$ 750,000
Long-term debt		5,630,000	5,630,000				$ 9,928,000
Principal maturities of long-term debt for 2021		524,000	524,000
Principal maturities of long-term debt for 2022		4,614,000	4,614,000
Principal maturities of long-term debt for 2023		231,000	231,000
Principal maturities of long-term debt for 2024		178,000	178,000
Principal maturities of long-term debt for 2025		77,000	77,000
Principal maturities of long-term debt for 2026		$ 6,000	$ 6,000
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
Debt Instrument, Face Amount						$ 4,000,000
Debt Instrument, Term	2 years
Percentage of PPP loan proceeds used to pay for payroll costs		60.00%
Gain on Paycheck Protection Program loan forgiveness		$ 4,057,000
Principle amount of Paycheck Protection Program loan forgiveness		4,000,000
Accrued interest amount of Paycheck Protection Program loan forgiveness		$ 57,000
Percentage of fixed interest rate payable		1.00%	1.00%
Lease term for equipment covered by lease line of credit	2 years
Line of credit payable to a financial institution; Interest rate option of bank prime or Libor plus 2.15% (B)(C)
Debt Instrument
Maximum borrowing capacity		$ 6,000,000	$ 6,000,000
Spread on variable rate			2.15%
Commitment fee on unused portion of line of credit			0.25%
Balance outstanding of line of credit		4,250,000	$ 4,250,000				3,750,000
Long-term debt		4,250,000	4,250,000				3,750,000
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 1.795535% - 1.835015% as of September 30, 2021.(D)
Debt Instrument
Maximum borrowing capacity					$ 1,000,000
Amount drawn			384,000
Balance outstanding of line of credit		$ 765,000	$ 765,000				534,000
Loan term for equipment covered by loan		60 months	60 months
Long-term debt		$ 765,000	$ 765,000				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 1.822758% - 1.869304% at time of funding)(E)
Debt Instrument
Debt Instrument, Term			60 months
Lease line of credit								$ 1,000,000
Lease term for equipment covered by lease line of credit			60 months
Long-term debt		$ 192,000	$ 192,000				$ 310,000