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Business combination cash paid in settlement of share based compensation awards.

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Business combination compensation expenses.

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Fair value increase of acquired property plant and equipment.

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Fair value write-up of acquired finished goods inventory.

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Incremental cost of sales charge.

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Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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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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Price of a single share of a number of saleable stocks paid or offered to be paid in a business combination.

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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 cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

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Acquisitions - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands		3 Months Ended
	Feb. 01, 2019	Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018
Business Acquisition [Line Items]
Business acquisition share price	$ 30.00
Stock-based compensation expense		$ 27,838	$ 10,426
Acquisition and integration costs		6,764
Electro Scientific Industries Inc [Member]
Business Acquisition [Line Items]
Business acquisition share price	$ 30.00
Business acquisition, total cash consideration	$ 1,032,671
Non Cash Consideration related to share based compensation awards	30,630
Total Purchase Consideration	$ 1,063,301
Fair value write-up of acquired finished goods inventory		8,383
Incremental costs of sales charge		5,140
Fair value write-up of acquired property, plant and equipment				$ 26,667
Compensation expense		2,701
Stock-based compensation expense		$ 14,023