Goodwill - Changes in Carrying Amount of Goodwill (Detail) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Goodwill [Line Items]
Beginning Balance	$ 454,612	$ 443,529
Currency impact		1,631
Goodwill acquired in acquisitions	167,945	9,452
Currency impact and other	(5,705)
Impairments	(182,542)	0	$ 0
Measurement period adjustments	5,142
Ending Balance	439,452	454,612	443,529
Mobile Solutions
Goodwill [Line Items]
Beginning Balance	74,147	73,263
Currency impact		884
Goodwill acquired in acquisitions	0	0
Currency impact and other	(705)
Impairments	(73,442)
Measurement period adjustments	0
Ending Balance	0	74,147	73,263
Power Solutions
Goodwill [Line Items]
Beginning Balance	202,681	201,934
Currency impact		747
Goodwill acquired in acquisitions	2,657	0
Currency impact and other	(1,882)
Impairments	(109,100)
Measurement period adjustments	149
Ending Balance	94,505	202,681	201,934
Life Sciences
Goodwill [Line Items]
Beginning Balance	177,784	168,332
Currency impact		0
Goodwill acquired in acquisitions	165,288	9,452
Currency impact and other	(3,118)
Impairments	0
Measurement period adjustments	4,993
Ending Balance	$ 344,947	$ 177,784	$ 168,332

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/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
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-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

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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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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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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.

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Amount of increase (decrease) from adjustments after acquisition date under purchase accounting 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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