Changes in Carrying Value of Goodwill (Detail) $ in Thousands	6 Months Ended
Jun. 30, 2020 USD ($)
Goodwill [Line Items]
Balance as of December 31, 2019	$ 468,413
Cumulative translation adjustment	19
Balance as of June 30, 2020	468,725
C Technologies, Inc.
Goodwill [Line Items]
Goodwill arising from Acquisition	293
Balance as of June 30, 2020	$ 142,314

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
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-SubTopic 210
-Section S99
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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.

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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.

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