Leases - Components of Lease Cost (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 16, 2020	Jun. 18, 2019	Jun. 16, 2020	Jun. 18, 2019
Leases [Abstract]
Operating lease cost	$ 9,363	$ 8,733	$ 18,809	$ 17,404
Finance lease cost:
Amortization of right of use assets	35	110	90	243
Interest on lease liabilities	6	24	18	51
Short-term lease cost	95	77	167	178
Variable lease cost	334	448	657	838
Sublease income	(1,690)	(1,134)	(3,272)	(2,136)
Total lease cost	$ 8,143	$ 8,258	$ 16,469	$ 16,578

Finance Lease, Costs

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- Definition

Amount of interest expense on finance lease liability.

+ References

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- Definition

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

+ References

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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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