Derivative Financial Instruments - Summary of Outstanding Commodity Derivative Agreements (Detail) - Commodity Hedging Agreements [Member] - USD ($)	12 Months Ended
Dec. 31, 2017	Jan. 01, 2017
Derivative Instruments And Hedging Activities Disclosures [Line Items]
Notional amount of outstanding commodity derivative agreements	$ 59,564,000	$ 13,146,000
Latest maturity date of outstanding commodity derivative agreements	2018-12	2017-12

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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