Leases - Schedule of Future Leases Obligations (Detail) - USD ($) $ in Thousands	Dec. 27, 2017	Dec. 28, 2016
Capital Leases, Minimum Lease Payments
December 26, 2018	$ 172
December 25, 2019	95
December 30, 2020	54
December 29, 2021	54
December 28, 2022	45
Thereafter	0
Total	420
Less: imputed interest (11.0% to 14.8%)	(104)
Present value of capital lease obligations	316
Less: current maturities	(132)	$ (144)
Noncurrent portion	184	$ 317
Capital Leases, Minimum Sublease Income
December 26, 2018	0
Capital lease, minimum sublease income	0
Operating Leases, Minimum Lease Payments
December 26, 2018	25,270
December 25, 2019	25,102
December 30, 2020	23,818
December 29, 2021	22,669
December 28, 2022	21,706
Thereafter	179,582
Total	298,147
Operating Leases, Minimum Sublease Income
December 26, 2018	932
December 25, 2019	728
December 30, 2020	455
December 29, 2021	466
December 28, 2022	466
Thereafter	1,158
Total	$ 4,205
Minimum
Capital Leases, Minimum Lease Payments
Imputed interest rate	11.00%
Maximum
Capital Leases, Minimum Lease Payments
Imputed interest rate	14.80%

Capital Leases Future Minimum Sublease Rentals, Fiscal Year Maturity [Abstract]

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Capital Leases Future Minimum Sublease Rentals, Next Twelve Months

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Operating Leases, Future Minimum Payments Due, Future Minimum Sublease Rentals, Next Twelve Months

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Operating Leases, Future Minimum Payments Due, Future Minimum Sublease Rentals, Thereafter

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Operating Leases, Future Minimum Payments Due, Future Minimum Sublease Rentals, within Five Years

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Operating Leases, Future Minimum Payments Due, Future Minimum Sublease Rentals, within Four Years

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Operating Leases, Future Minimum Payments Due, Future Minimum Sublease Rentals, within Three Years

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Operating Leases, Future Minimum Payments Due, Future Minimum Sublease Rentals, within Two Years

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Amount of capital lease obligation due within one year or the normal operating cycle, if longer.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 30
-Section 50
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Amount equal to the present value (the principal) at the beginning of the lease term of minimum lease payments during the lease term (excluding that portion of the payments representing executory costs such as insurance, maintenance, and taxes to be paid by the lessor, together with any profit thereon) net of payments or other amounts applied to the principal, through the balance sheet date and due to be paid more than one year (or one operating cycle, if longer) after the balance sheet date.

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Amount of minimum lease payments for capital leases.

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Amount of minimum lease payments for capital leases due in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of minimum lease payments for capital leases due in the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of minimum lease payments for capital leases due in the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of minimum lease payments for capital leases due in the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of minimum lease payments for capital leases due after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount necessary to reduce net minimum lease payments to present value for capital leases.

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Present value of minimum lease payments for capital leases net of executory costs, including amounts paid by the lessee to the lessor for insurance, maintenance and taxes.

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Minimum payments receivable in the future under noncancelable subleases.

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The percentage points added to the reference rate to compute the variable rate on the lessee's capital lease.

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Amount of required minimum rental payments for leases having an initial or remaining non-cancelable letter-terms in excess of one year.

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Contractually required future rental payments receivable on noncancelable subleasing arrangements.

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