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

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States whether the entity was in compliance with the debt covenants throughout the reporting period, and describes facts and circumstances of any compliance failure.

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Description of minimum financial levels (for example, tangible net worth and working capital) and achievement of certain financial ratios (for example, working capital ratio and debt service coverage ratio), and adherence to certain clauses which generally require or restrict certain actions (for example, entering into a debt arrangement with equal or greater seniority, and selling or discontinuing a certain business segment or material subsidiary) to be in compliance with the covenant clauses of the debt agreement. May also include a discussion of the adverse consequences that would result if the entity violates or fails to satisfy the covenants.

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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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Description of the frequency of periodic payments (monthly, quarterly, annual).

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

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Description of the interest rate as being fixed or variable, and, if variable, identification of the index or rate on which the interest rate is based and the number of points or percentage added to that index or rate to set the rate, and other pertinent information, such as frequency of rate resets.

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Date the debt instrument was issued, in CCYY-MM-DD format.

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Identification of the contractual issuer of the debt instrument (for example, a subsidiary of the reporting entity).

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

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Description of the maturity date of the debt instrument including whether the debt matures serially and, if so, a brief description of the serial maturities.

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Amount of the required periodic payments applied to principal.

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Description of debt redemption features under terms of the debt agreement.

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Description of unused borrowing capacity under the debt instrument and conditions under which the commitment can be withdrawn by the lender.

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Disclosure of timing of required repayments, sinking fund requirements, and other redeemable securities at fixed or determinable prices and dates in the five years immediately following the date of the latest balance sheet presented in the financial statements, and the amount thereafter to fully repay the principal of long-term debt. These disclosures may be made either on an individual debt or security basis, by type of debt or security basis, or on a combined basis.

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

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The cash inflow from a contractual arrangement with the lender, including letter of credit, standby letter of credit and revolving credit arrangements, under which borrowings can be made up to a specific amount at any point in time with maturities due beyond one year or the operating cycle, if longer.

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Debt - Wells Fargo Term Loans (Narrative) (Details) - USD ($)		12 Months Ended
	Oct. 28, 2020	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Debt
Proceeds from term loan		$ 30,165,000	$ 0	$ 45,000,000
Repayments of Long-term Debt		$ 38,725,000	$ 3,375,000	$ 10,125,000
Term loans payable \| Wells Fargo Bank, National Association
Debt
Debt Instrument, Issuance Date		Oct. 27, 2020
Debt Instrument, Issuer		Wells Fargo Bank, National Association
Debt Instrument, 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 secured term loans (the “WF Term Loans”) in the maximum aggregate principal amount of $18,500,000 ($16,790,000 of which was advanced to the Company on October 28, 2020).
Debt Instrument, Face Amount		$ 18,500,000
Debt Instrument, Unused Borrowing Capacity, Description		the maximum aggregate principal amount of $18,500,000 ($16,790,000 of which was advanced to the Company on October 28, 2020).
Proceeds from term loan	$ 16,790,000
Debt Instrument, Interest Rate Terms		At the option of the Company, the WF Term Loans bears interest at a per annum rate equal to LIBOR plus a margin of 300 basis points or base rate plus a margin of 200 basis points. 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 or (d) prime rate. The weighted average interest rate was 3.77% as of December 31, 2020.
Long-term Debt, Weighted Average Interest Rate, at Point in Time		3.77%
Long-term Debt, Maturities, Repayment Terms		The WF Term Loans are to be repaid in monthly installments of $200,000 plus interest, with the remaining outstanding balance due on November 30, 2024, subject to certain optional and mandatory repayment terms. The Company’s obligations under the WF Term Loans are unconditionally guaranteed by each of the Company’s U.S. and Canadian subsidiaries, with such obligations of the Company and such subsidiaries being secured by a lien on substantially all of their U.S. and Canadian assets.
Debt Instrument, Frequency of Periodic Payment		monthly
Debt Instrument, Periodic Payment, Principal		$ 200,000
Debt Instrument, Maturity Date, Description		the remaining outstanding balance due on November 30, 2024, subject to certain optional and mandatory repayment terms.
Debt Instrument, Maturity Date		Nov. 30, 2024
Debt Instrument, Covenant Description		The WF Term Loans contains reporting, indebtedness, and financial covenants.
Debt Instrument, Covenant Compliance		The Company is in compliance with its covenants as of December 31, 2020.
Debt Instrument, Redemption, Description		Voluntary prepayments of amounts outstanding under the WF Term Loans are permitted at any time without premium or penalty. To the extent applicable, LIBOR breakage fees may be charged in connection with any prepayment.
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, Interest Rate Terms		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		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, Interest Rate Terms		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 or (d) prime rate.
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%