Changes in Carrying Value of Goodwill (Detail) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019
Goodwill [Line Items]
Balance	$ 468,413	$ 326,735
Cumulative translation adjustment	1,572	(343)
Balance	618,305	468,413
C Technologies
Goodwill [Line Items]
Goodwill arising from Acquisition	12,585	$ 142,021
Balance	142,314
Spectrum Inc.
Goodwill [Line Items]
Goodwill arising from Acquisition	293
NMS
Goodwill [Line Items]
Goodwill arising from Acquisition	6,784
Balance	6,784
ARTeSYN
Goodwill [Line Items]
Goodwill arising from Acquisition	128,658
Balance	$ 128,658

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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