Note 4 - Leases - Lease Expense (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jul. 04, 2021	Jul. 05, 2020	Jul. 04, 2021	Jul. 05, 2020
Amortization expense	$ 87	$ 108	$ 173	$ 228
Interest expense	59	72	117	149
Operating lease expense	351	351	702	702
Variable lease expense	76	94	154	162
Total lease expense	$ 573	$ 625	$ 1,146	$ 1,241

Amount of interest expense on finance lease liability.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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-Section 50
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Amount of amortization expense attributable to right-of-use asset from finance lease.

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- Definition

Amount of lease cost recognized by lessee for lease contract.

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Amount of single lease cost, calculated by allocation of remaining cost of lease over remaining lease term. Includes, but is not limited to, single lease cost, after impairment of right-of-use asset, calculated by amortization of remaining right-of-use asset and accretion of lease liability.

+ References

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Amount of variable lease cost, excluded from lease liability, recognized when obligation for payment is incurred for finance and operating leases.

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