Note 11 - Leases - Lease Expense (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 24, 2022	Sep. 25, 2021	Sep. 24, 2022	Sep. 25, 2021
Operating leases	$ 1,654	$ 1,799	$ 5,046	$ 5,866
Variable lease expense	520	508	1,583	1,634
Short-term operating leases	1	1	3	68
Amortization of leased assets	11	21	69	66
Interest on lease liabilities	0	0	1	1
Sublease income	(16)	(21)	(54)	(61)
Net lease cost	$ 2,170	$ 2,308	$ 6,648	$ 7,574

Amount of interest expense on finance lease liability.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 20
-Section 50
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 3: http://www.xbrl.org/2003/role/exampleRef
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-Name Accounting Standards Codification
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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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-Publisher FASB
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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 short-term lease cost, excluding expense for lease with term of one month or less.

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Amount of sublease income excluding finance and operating lease expense.

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- Definition

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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