Business combination consideration transferred equity interests issued and issuable fair value.

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- Definition

Business combination step acquisition step up of inventory to fair value.

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Weighted average amortization period of finite-lived intangible assets acquired either individually or as part of a group of assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Amount of direct costs of the business combination including legal, accounting, and other costs incurred to consummate the business acquisition.

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Value of equity interests (such as common shares, preferred shares, or partnership interest) issued or issuable to acquire the entity.

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Number of shares of equity interests issued or issuable to acquire entity.

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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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Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

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The net result for the period of deducting operating expenses from operating revenues.

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Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

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Business Combination - Textual (Details) - USD ($) shares in Thousands, $ in Thousands		12 Months Ended
	Oct. 25, 2019	Dec. 26, 2020	Dec. 31, 2019	Dec. 31, 2018
Business Acquisition [Line Items]
Net sales		$ 556,496	$ 305,896	$ 273,784
Operating loss		(26,677)	5,043	$ (51,084)
Rudolph Technologies, Inc. [Member]
Business Acquisition [Line Items]
Business combination aggregate purchase price		$ 890,131
Step-up of inventory to fair value as of merger date	$ 26,486
Net sales			66,261
Operating loss			7,065
Rudolph Technologies, Inc. [Member] \| Developed technology [Member]
Business Acquisition [Line Items]
Estimated useful life		6 years 7 months 6 days
Rudolph Technologies, Inc. [Member] \| Customer relationships [Member]
Business Acquisition [Line Items]
Estimated useful life		13 years 1 month 6 days
Rudolph Technologies, Inc. [Member] \| Backlog [Member]
Business Acquisition [Line Items]
Estimated useful life		1 year 1 month 6 days
Rudolph Technologies, Inc. [Member] \| Trademarks and trade names [Member]
Business Acquisition [Line Items]
Estimated useful life		7 years 6 months
Rudolph Technologies, Inc. [Member] \| Common Stock [Member]
Business Acquisition [Line Items]
Business combination equity interests issued or issuable		$ 884,801
Business combination common stock shares issued		25,060
Rudolph Technologies, Inc. [Member] \| Nanometrics Equity Awards [Member]
Business Acquisition [Line Items]
Business combination fair value of assumed equity awards included in aggregate purchase		$ 5,330
Rudolph Technologies, Inc. [Member] \| General and Administrative Expense [Member]
Business Acquisition [Line Items]
Business acquisition, related costs			$ 9,907