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Description of the conditions for borrowing under the credit facility including the nature of any restrictions.

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Amount of current borrowing capacity under the credit facility considering any current restrictions on the amount that could be borrowed (for example, borrowings may be limited by the amount of current assets), but without considering any amounts currently outstanding under the facility.

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Description of the terms of a credit facility arrangement. Terms typically include interest rate, collateral required, guarantees required, repayment requirements, and restrictions on use of assets and activities of the entity.

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Date the credit facility terminates, in CCYY-MM-DD format.

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Description of the interest rate for the amounts borrowed under the credit facility, including the terms and the method for determining the interest rate (for example, fixed or variable, LIBOR plus a percentage, increasing rate, timing of interest rate resets, remarketing provisions).

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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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Weighted average interest rate of long-term debt outstanding calculated at point in time.

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Debt - Wells Fargo Revolving Loan (Narrative) (Details) - USD ($)			12 Months Ended
	Oct. 28, 2020	Oct. 27, 2020	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Debt
Proceeds from Lines of Credit			$ 56,793,000	$ 194,414,000	$ 133,848,000
Repayments of Long-term Debt			38,725,000	3,375,000	$ 10,125,000
Debt origination fees, Gross			$ 1,957,000	$ 807,000
Incremental revolving commitment
Debt
Line of Credit Facility, Description			The Credit Agreement also makes available to the Company an incremental revolving commitment in the maximum amount of $10,000,000 at the Company’s option at any time during the three (3) year period following the closing.
Term loans payable \| Wells Fargo Bank, National Association
Debt
Long-term Debt, Weighted Average Interest Rate, at Point in Time			3.77%
Debt origination fees, gross, line of credit facility			$ 1,730,000
Term loans payable \| Wells Fargo Bank, National Association \| KeyBank National Association
Debt
Repayments of Long-term Debt	$ 16,790,000
Term loans payable \| Wells Fargo Bank, National Association \| Libor Rate
Debt
Debt Instrument, Description of Variable Rate Basis			LIBOR
Debt Instrument, Basis Spread on Variable Rate			3.00%
Term loans payable \| Wells Fargo Bank, National Association \| Libor Rate \| Minimum
Debt
Debt Instrument, Basis Spread on Variable Rate			1.00%
Debt Instrument, Interest Rate, Stated Percentage			0.75%
Term loans payable \| Wells Fargo Bank, National Association \| Base Rate
Debt
Debt Instrument, Description of Variable Rate Basis			base rate
Debt Instrument, Basis Spread on Variable Rate			2.00%
Term loans payable \| Wells Fargo Bank, National Association \| Base Rate \| Minimum
Debt
Debt Instrument, Interest Rate, Stated Percentage			1.00%
Term loans payable \| Wells Fargo Bank, National Association \| Federal Funds Rate
Debt
Debt Instrument, Basis Spread on Variable Rate			0.50%
Term loans payable \| FGI Equipment Finance LLC Term Loan
Debt
Debt Instrument, Interest Rate, Stated Percentage			8.25%
Debt origination fees, Gross			$ 308,000
Term loans payable \| FGI Equipment Finance LLC Term Loan \| KeyBank National Association
Debt
Repayments of Long-term Debt		$ 12,000,000
Revolving loans \| Wells Fargo Bank, National Association
Debt
Line of Credit Facility, Initiation Date			Oct. 27, 2020
Line of Credit Facility, Description			On October 27, 2020, the Company entered into a credit agreement (the “Credit Agreement”) with Wells Fargo Bank, National Association, as administrative agent, lead arranger and book runner, and the lenders party thereto (the “Lenders”). Pursuant to the terms of the Credit Agreement, the Lenders made available to the Company a revolving loan commitment (the “WF Revolving Loan”) of $25,000,000 ($8,745,000 of which was advanced to the Company on October 28, 2020).
Maximum borrowing capacity			$ 25,000,000
Line of Credit Facility, Borrowing Capacity, Description			The borrowing availability under the line of credit is the lesser of (a) the loan commitment of $25,000,000 or (b) the sum of 90% of eligible investment grade accounts receivable, 85% of non-investment grade eligible accounts receivable and 65% of eligible inventory.
Proceeds from Lines of Credit	8,745,000
Line of Credit Facility, Interest Rate Description			At the option of the Company, the WF Revolving Loan bears interest at a per annum rate equal to LIBOR plus a margin of 200 to 250 basis points or base rate plus a margin of 100 to 150 basis points, with the margin rate being based on the excess availability amount under the line of credit. LIBOR rate means the greater of (a) 0.75% per annum and (b) the per annum published LIBOR rate for interest periods of one, three or six months as chosen by the Company. Base rate is the greater of (a) 1.0% per annum, (b) the Federal Funds Rate plus 0.5%, (c) LIBOR Rate plus 100 basis and (d) prime rate. The weighted average interest rate was 4.75% as of December 31, 2020.
Long-term Debt, Weighted Average Interest Rate, at Point in Time			4.75%
Line of Credit Facility, Expiration Date			Nov. 30, 2024
Line of Credit Facility, Frequency of Payment and Payment Terms			The WF Revolving Loan commitment terminates, and all outstanding borrowings thereunder must be repaid, by November 30, 2024.
Current Borrowing Capacity			$ 19,223,000
Revolving Line of Credit			$ 420,000
Line of Credit Facility, Covenant Terms			The WF Revolving Loan contains the same covenants as the WF Term Loans.
Line of Credit Facility, Covenant Compliance			The Company is in compliance with its covenants as of December 31, 2020.
Letters of Credit Outstanding, Amount			$ 160,000
Debt origination fees, Gross			1,957,000
Revolving loans \| Wells Fargo Bank, National Association \| Letter of Credit [Member]
Debt
Maximum borrowing capacity			$ 2,000,000
Revolving loans \| Wells Fargo Bank, National Association \| Eligible investment grade \| Accounts Receivable
Debt
Borrowing availability under the line of credit			90.00%
Revolving loans \| Wells Fargo Bank, National Association \| Eligible investment grade \| Inventories
Debt
Borrowing availability under the line of credit			65.00%
Revolving loans \| Wells Fargo Bank, National Association \| Non-investment grade eligible \| Accounts Receivable
Debt
Borrowing availability under the line of credit			85.00%
Revolving loans \| Wells Fargo Bank, National Association \| KeyBank National Association
Debt
Repayments of Long-term Debt	$ 8,745,000
Revolving loans \| Wells Fargo Bank, National Association \| Libor Rate
Debt
Line of Credit Facility, Interest Rate Description			LIBOR rate means the greater of (a) 0.75% per annum and (b) the per annum published LIBOR rate for interest periods of one, three or six months as chosen by the Company.
Debt Instrument, Description of Variable Rate Basis			LIBOR
Debt Instrument, Basis Spread on Variable Rate			1.00%
Revolving loans \| Wells Fargo Bank, National Association \| Libor Rate \| Minimum
Debt
Debt Instrument, Basis Spread on Variable Rate			2.00%
Debt Instrument, Interest Rate, Stated Percentage			0.75%
Revolving loans \| Wells Fargo Bank, National Association \| Libor Rate \| Maximum
Debt
Debt Instrument, Basis Spread on Variable Rate			2.50%
Revolving loans \| Wells Fargo Bank, National Association \| Base Rate
Debt
Line of Credit Facility, Interest Rate Description			Base rate is the greater of (a) 1.0% per annum, (b) the Federal Funds Rate plus 0.5%, (c) LIBOR Rate plus 100 basis and (d) prime rate.
Debt Instrument, Description of Variable Rate Basis			base rate
Revolving loans \| Wells Fargo Bank, National Association \| Base Rate \| Minimum
Debt
Debt Instrument, Basis Spread on Variable Rate			1.00%
Debt Instrument, Interest Rate, Stated Percentage			1.00%
Revolving loans \| Wells Fargo Bank, National Association \| Base Rate \| Maximum
Debt
Debt Instrument, Basis Spread on Variable Rate			1.50%
Revolving loans \| Wells Fargo Bank, National Association \| Federal Funds Rate
Debt
Debt Instrument, Basis Spread on Variable Rate			0.50%
Revolving loans \| Incremental revolving commitment
Debt
Maximum borrowing capacity			$ 10,000,000