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Acquisition - Schedule of Unaudited Pro Forma Financial Information (Detail) - Electro Scientific Industries Inc [Member] - USD ($) $ / shares in Units, $ in Millions | 12 Months Ended
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Dec. 31, 2019 | Dec. 31, 2018
Acquisition Date [Line Items] |  |
Total net revenues | $ 1,914.6 | $ 2,445.7
Net income | $ 171.5 | $ 424.8
Net income per share: |  |
Basic | $ 3.14 | $ 7.81
Diluted | $ 3.11 | $ 7.72

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- Definition The pro forma basic net income per share for a period as if the business combination or combinations had been completed at the beginning of a period. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (h)(3) -URI http://asc.fasb.org/extlink&oid=79982066&loc=d3e1392-128463 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (h)(2) -URI http://asc.fasb.org/extlink&oid=79982066&loc=d3e1392-128463 + Details
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