Organization and Significant Accounting Policies - Additional Information (Detail)	9 Months Ended	12 Months Ended
Sep. 25, 2020 USD ($) Segment Customer	Dec. 27, 2019 Customer
Concentration Risk [Line Items]
Number of operating segments	2
Number of reportable segments	2
Impairments of goodwill and intangible assets \| $	$ 0
Customer Concentration Risk [Member] \| Lam Research Corporation, Applied Materials, Inc. and ASM International, Inc. [Member]
Concentration Risk [Line Items]
Number of customers with accounts receivable greater than 10% \| Customer	3	3
Customer Concentration Risk [Member] \| Lam Research Corporation, Applied Materials, Inc. and ASM International, Inc. [Member] \| Accounts Receivable [Member]
Concentration Risk [Line Items]
Concentration percentage	59.10%	66.70%
Cinos Co., Ltd [Member]
Concentration Risk [Line Items]
Noncontrolling interest, ownership percentage by parent	86.00%
Cinos Xian Clean Technology, Ltd [Member]
Concentration Risk [Line Items]
Noncontrolling interest, ownership percentage by parent	60.00%
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	50 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	10 years

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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.

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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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Total loss recognized during the period from the impairment of goodwill plus the loss recognized in the period resulting from the impairment of the carrying amount of intangible assets, other than goodwill.

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The parent entity's interest in net assets of the subsidiary, expressed as a percentage.

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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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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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