Revenue Recognition - Additional Information (Detail) $ in Millions	6 Months Ended	12 Months Ended
Jun. 29, 2018 USD ($) Segment Customer	Dec. 29, 2017 Customer
Concentration Risk [Line Items]
Number of reportable segments \| Segment	1
Accrued Expenses [Member]
Concentration Risk [Line Items]
Unpaid customer rebates \| $	$ 0.7
Maximum [Member]
Concentration Risk [Line Items]
Product warranty period (in years)	2 years
Customer Concentration Risk [Member] \| Lam Research Corporation and Applied Materials, Inc. [Member]
Concentration Risk [Line Items]
Number of customers with accounts receivable greater than 10% \| Customer	2	2
Customer Concentration Risk [Member] \| Lam Research Corporation and Applied Materials, Inc. [Member] \| Accounts Receivable [Member]
Concentration Risk [Line Items]
Concentration percentage	70.60%	75.80%

Number of customers with accounts receivable greater than ten percent.

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- Definition

Products Warranty Period

+ References

No definition available.

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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.

+ References

No definition available.

+ Details

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- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition

Current regulatory liabilities generally represent obligations to make refunds to customers for various reasons including overpayment.

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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.

+ References

No definition available.

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