Goodwill - Changes in Carrying Amount of Goodwill (Detail) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Goodwill [Line Items]
Beginning Balance	$ 94,779	$ 94,505
Currency impact and other	(1,837)	274
Impairments	(92,942)	0	$ (182,542)
Ending Balance	0	94,779	$ 94,505
Mobile Solutions
Goodwill [Line Items]
Beginning Balance	0
Ending Balance	0	0
Power Solutions
Goodwill [Line Items]
Beginning Balance	94,779
Ending Balance	$ 0	$ 94,779

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.

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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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Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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