Product Warranties - Product Warranty Activities (Detail) - USD ($) $ in Millions	9 Months Ended
Sep. 30, 2020	Sep. 30, 2019
Product Warranty Liability [Line Items]
Beginning of period	$ 14.9	$ 10.4
Provision for product warranties	20.2	18.7
Charges to warranty liability	(19.0)	(21.2)
End of period	$ 16.1	15.1
Electro Scientific Industries Inc [Member]
Product Warranty Liability [Line Items]
Assumed product warranty liability from ESI Merger		$ 7.2

Liability for an extended product warranty acquired in a business acquisition. Does not include any liability for a standard warranty acquired in a business acquisition.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 8
-Subparagraph (c)(4)
-URI http://asc.fasb.org/extlink&oid=68068213&loc=d3e12565-110249

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- Definition

Carrying value as of the balance sheet date of obligations incurred through that date and payable for estimated claims under standard and extended warranty protection rights granted to customers.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.15(5))
-URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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-Topic 460
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- Definition

Amount of increase (decrease) in the standard and extended product warranty liability.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 8
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Amount of increase in the standard and extended product warranty accrual from warranties issued.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 8
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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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