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

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Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset.

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Fixed interest rate related to the interest rate derivative.

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Nominal or face amount used to calculate payments on the derivative liability.

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Fixed interest rate that will be received or paid upon exercise of the interest rate swaption contract.

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Note 6 - Long-term Debt (Details Textual) $ in Thousands				12 Months Ended
Note 6 - Long-term Debt (Details Textual) $ in Thousands	Sep. 27, 2019	Sep. 26, 2019	Jan. 22, 2019 USD ($)	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	May 02, 2018 USD ($)	May 01, 2018 USD ($)	Mar. 01, 2018 USD ($)	Feb. 28, 2017 USD ($)
Repayments of Long-term Debt, Total				$ 163,645	$ 127,439	$ 77,573
Long-term Debt, Maturities, Repayments of Principal in Year Two				15,286
Derivative, Fixed Interest Rate									3.12%
Long-term Debt, Maturities, Repayments of Principal in Year Four				53,124
Long-term Debt, Maturities, Repayments of Principal in Year Three				15,286
Long-term Debt, Maturities, Repayments of Principal in Year Five				10,786
Interest Rate Swap [Member]
Derivative Liability, Notional Amount									$ 18,000
Derivative, Notional Amount, Monthly Reduction Amount									$ 300
Derivative, Swaption Interest Rate								3.05%
Interest Rate Swap [Member] \| Other Current Liabilities [Member]
Derivative Liability, Notional Amount								$ 17,500
Derivative Liability, Total							$ 100
Interest Rate Swap [Member] \| Prepaid Expenses and Other Current Assets [Member]
Derivative Asset, Total				200
Credit Agreement [Member]
EBITA Ratio	5	4
Fixed Charge Coverage Ratio			1.25
Credit Agreement [Member] \| Term Loan [Member]
Debt Instrument, Face Amount			$ 65,000							$ 42,000
Repayments of Long-term Debt, Total			$ 20,000
Long-term Debt, Maturities, Repayments of Principal, Remainder of Fiscal Year				6,000
Long Term Debt Maturities Repayments of Principal in Year Six				1,500
Long-term Debt, Maturities, Repayments of Principal in Year Two				$ 6,000
Debt Instrument, Interest Rate, Effective Percentage				2.43%
Long-term Debt, Maturities, Repayments of Principal in Year Four				$ 6,000
Long-term Debt, Maturities, Repayments of Principal in Year Three				6,000
Long-term Debt, Maturities, Repayments of Principal in Year Five				$ 6,000
Credit Agreement [Member] \| Term Loan [Member] \| Minimum [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument, Basis Spread on Variable Rate				0.68%
Credit Agreement [Member] \| Term Loan [Member] \| Maximum [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument, Basis Spread on Variable Rate				1.50%
Credit Agreement [Member] \| Term Loan 2 [Member]
Debt Instrument, Face Amount							85,000
Long Term Debt Maturities Repayments of Principal in Year Six				$ 9,300
Long-term Debt, Maturities, Repayments of Principal in Year Two				9,300
Long Term Debt Maturities Repayments of Principal in Year Eight				$ 800
Debt Instrument, Interest Rate, Effective Percentage				2.60%
Long-term Debt, Maturities, Repayments of Principal in Year Four				$ 9,300
Long-term Debt, Maturities, Repayments of Principal in Year Three				9,300
Long-term Debt, Maturities, Repayments of Principal in Year Five				9,300
Long Term Debt Maturities Repayments of Principal in Year Seven				$ 9,300
Credit Agreement [Member] \| Term Loan 2 [Member] \| Minimum [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument, Basis Spread on Variable Rate				0.85%
Credit Agreement [Member] \| Term Loan 2 [Member] \| Maximum [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument, Basis Spread on Variable Rate				1.65%
Credit Agreement [Member] \| Revolving Credit Facility [Member]
Line of Credit Facility, Maximum Borrowing Capacity										$ 35,000
Credit Agreement [Member] \| Revolving Credit Facility [Member] \| Fifth Third Bank [Member]
Line of Credit Facility, Maximum Borrowing Capacity								$ 35,000
Credit Agreement [Member] \| Revolving Credit Facility [Member] \| BB&T [Member]
Line of Credit Facility, Maximum Borrowing Capacity							$ 75,000