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Debt - Revolving Loans (Narrative) (Details) - USD ($)			3 Months Ended
	Oct. 28, 2020	Oct. 27, 2020	Mar. 31, 2022	Mar. 31, 2021	Dec. 31, 2021
Debt Instrument [Line Items]
Principal amount advanced			$ 1,092,000	$ 688,000
Loan balance			25,580,000		$ 26,672,000
Wells Fargo term loans payable
Debt Instrument [Line Items]
Loan balance			$ 13,392,000		$ 13,992,000
Revolving Credit Facility | Incremental Revolving Commitment
Debt Instrument [Line Items]
Revolving loan commitment		$ 10,000,000
Debt term		3 years
Revolving Credit Facility | Wells Fargo term loans payable
Debt Instrument [Line Items]
Revolving loan commitment		$ 25,000,000
Weighted average interest rate			4.50%		4.25%
Available rate revolving loans			$ 24,316,000	$ 1,351,000	$ 24,337,000
Letters of credit outstanding			$ 160,000
Revolving Credit Facility | Wells Fargo term loans payable | Letter of Credit
Debt Instrument [Line Items]
Revolving loan commitment		$ 2,000,000
Revolving Credit Facility | Wells Fargo term loans payable | Investment Grade | Accounts Receivable
Debt Instrument [Line Items]
Eligible investment grade		90.00%
Revolving Credit Facility | Wells Fargo term loans payable | Investment Grade | Inventories
Debt Instrument [Line Items]
Eligible investment grade		65.00%
Revolving Credit Facility | Wells Fargo term loans payable | Non Investment Grade | Accounts Receivable
Debt Instrument [Line Items]
Eligible investment grade		85.00%
Revolving Credit Facility | Wells Fargo term loans payable | Keybank National Association
Debt Instrument [Line Items]
Principal amount advanced	$ 8,745,000
Revolving Credit Facility | LIBOR | Wells Fargo term loans payable
Debt Instrument [Line Items]
Basis points		1.00%
Revolving Credit Facility | LIBOR | Wells Fargo term loans payable | Minimum
Debt Instrument [Line Items]
Basis points		2.00%
Stated interest rate		0.75%
Revolving Credit Facility | LIBOR | Wells Fargo term loans payable | Maximum
Debt Instrument [Line Items]
Basis points		2.50%
Revolving Credit Facility | Base Rate | Wells Fargo term loans payable | Minimum
Debt Instrument [Line Items]
Basis points		1.00%
Stated interest rate		1.00%
Revolving Credit Facility | Base Rate | Wells Fargo term loans payable | Maximum
Debt Instrument [Line Items]
Basis points		1.50%
Revolving Credit Facility | Federal Funds Rate | Wells Fargo term loans payable
Debt Instrument [Line Items]
Basis points		0.50%
Loans Payable | Wells Fargo term loans payable
Debt Instrument [Line Items]
Weighted average interest rate			3.78%		3.77%
Loans Payable | Wells Fargo term loans payable | Keybank National Association
Debt Instrument [Line Items]
Principal amount advanced	$ 16,790,000
Loans Payable | LIBOR | Wells Fargo term loans payable
Debt Instrument [Line Items]
Basis points		3.00%
Stated interest rate		0.75%
Loans Payable | LIBOR | Wells Fargo term loans payable | Minimum
Debt Instrument [Line Items]
Basis points		1.00%
Loans Payable | Base Rate | Wells Fargo term loans payable
Debt Instrument [Line Items]
Basis points		2.00%
Stated interest rate		1.00%
Loans Payable | Federal Funds Rate | Wells Fargo term loans payable
Debt Instrument [Line Items]
Basis points		0.50%

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

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