Organization and Significant Accounting Policies - Additional Information (Detail)	6 Months Ended
Jun. 29, 2018 Segment
Concentration Risk [Line Items]
Number of operating segments	1
Number of reportable segments	1
Minimum [Member]
Concentration Risk [Line Items]
Fiscal year duration	364 days
Useful lives range	3 years
Minimum [Member] \| Internal Use Software [Member]
Concentration Risk [Line Items]
Useful lives range	3 years
Maximum [Member]
Concentration Risk [Line Items]
Fiscal year duration	371 days
Useful lives range	15 years
Measurement period to determine fair value of assets and liabilities	12 months
Maximum [Member] \| Internal Use Software [Member]
Concentration Risk [Line Items]
Useful lives range	5 years

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- Definition

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.

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Duration of a fiscal period, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Includes, but not limited to, weeks in a year or quarter.

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Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues.

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- Definition

Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

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Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

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