Supplemental Financial Information - Income Statement Accounts (Detail) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Currency Transaction Gains (Losses) [Line Items]
Currency transaction losses, net	$ (21,539)	$ (363)	$ (8,389)
Design and development	189,494	197,226	205,368
Identifiable intangible asset amortization	38,925	40,112	39,095
Bad debt expense, net	9,149	967	40,894
Operating Income (Loss)
Currency Transaction Gains (Losses) [Line Items]
Currency transaction losses, net	(20,843)	164	(5,061)
Other non-operating expense, net
Currency Transaction Gains (Losses) [Line Items]
Currency transaction losses, net	$ (696)	$ (527)	$ (3,328)

Currency Transaction Gains (Losses) [Line Items]

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The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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Amount before tax of foreign currency transaction realized and unrealized gain (loss) recognized in the income statement.

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Amount of expense (reversal of expense) for expected credit loss on accounts receivable.

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The aggregate costs incurred (1) in a planned search or critical investigation aimed at discovery of new knowledge with the hope that such knowledge will be useful in developing a new product or service, a new process or technique, or in bringing about a significant improvement to an existing product or process; or (2) to translate research findings or other knowledge into a plan or design for a new product or process or for a significant improvement to an existing product or process whether intended for sale or the entity's use, during the reporting period charged to research and development projects, including the costs of developing computer software up to the point in time of achieving technological feasibility, and costs allocated in accounting for a business combination to in-process projects deemed to have no alternative future use.

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