Note 11 - Leases - Lease Expense (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 26, 2022	Mar. 27, 2021
Operating leases	$ 1,716	$ 2,040
Variable lease expense	537	552
Short-term operating leases	1	33
Amortization of leased assets	32	21
Sublease income	(20)	(19)
Net lease cost	$ 2,266	$ 2,627

Amount of amortization expense attributable to right-of-use asset from finance lease.

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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 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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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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