Goodwill - Changes in the Carrying Value of Goodwill (Detail) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019
Goodwill [Roll Forward]
Goodwill, Beginning Balance	$ 243,445	$ 113,208
Foreign exchange rate changes	1,637	95
Goodwill, Ending Balance	244,078	243,445
Sualab Co., Ltd. [Member]
Goodwill [Roll Forward]
Goodwill acquired during the period		$ 130,142
Goodwill, Other Increase (Decrease)	$ (1,004)

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
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-Section S99
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- Definition

Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

+ References

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- Definition

Amount of foreign currency translation gain (loss) which increases (decreases) an asset representing future economic benefits from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

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Amount of increase (decrease), classified as other, of an asset representing the future economic benefits from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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No definition available.

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