Leases (Maturities of lease liabilities) (Detail) - USD ($) $ in Thousands	Mar. 30, 2019	Dec. 30, 2018
Operating Leases
2019	$ 3,482
2020	4,946
2021	4,809
2022	4,513
2023	4,395
After 2023	13,179
Total lease payments	35,324
Less imputed interest	(4,436)
Present Value of Lease liability	$ 30,888	$ 31,500
Lease Weighted Average Remaining Lease Term	7 years 6 months
Operating lease weighted average discount rate	3.40%

Discount rate used by lessee to determine present value of operating lease payments.

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Amount of lessee's undiscounted obligation for lease payments for operating lease.

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Amount of lessee's undiscounted obligation for lease payments for operating lease, due after fifth fiscal year following latest fiscal year.

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Amount of lessee's undiscounted obligation for lease payments for operating lease, due in fifth fiscal year following latest fiscal year.

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Amount of lessee's undiscounted obligation for lease payments for operating lease, due in third fiscal year following latest fiscal year.

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Amount of lessee's undiscounted obligation for lease payments for operating lease, due in second fiscal year following latest fiscal year.

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Amount of lessee's undiscounted obligation for lease payments for operating lease having an initial or remaining lease term in excess of one year due in remainder of fiscal year following latest fiscal year.

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Amount of lessee's undiscounted obligation for lease payments in excess of discounted obligation for lease payments for operating lease.

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Present value of lessee's discounted obligation for lease payments from operating lease.

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Weighted average remaining lease term for operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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