Note 9 - Leases - Lease Expense (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 29, 2019	Jun. 29, 2019
Operating leases	$ 2,139	$ 4,261
Variable leases	635	1,201
Short-term operating leases	66	144
Amortization of leased assets	21	62
Interest on lease liabilities	29	88
Sublease income	(34)	(70)
Net lease cost	$ 2,856	$ 5,686

Amount of interest expense on finance lease liability.

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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.

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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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