Intangible Assets, Net - Summary of Carrying Amount of Intangible Assets by Segment (Detail) $ in Thousands	9 Months Ended
Sep. 30, 2018 USD ($)
Finite-lived Intangible Assets [Roll Forward]
Beginning Balance	$ 237,702
Amortization	(24,114)
Currency impacts	(22)
Intangible assets acquired in acquisition	171,817
Measurement period adjustments	(700)
Ending balance	384,683
Mobile Solutions
Finite-lived Intangible Assets [Roll Forward]
Beginning Balance	39,446
Amortization	(2,655)
Currency impacts	(22)
Intangible assets acquired in acquisition	0
Measurement period adjustments	0
Ending balance	36,769
Power Solutions
Finite-lived Intangible Assets [Roll Forward]
Beginning Balance	105,030
Amortization	(8,746)
Currency impacts	0
Intangible assets acquired in acquisition	1,900
Measurement period adjustments	0
Ending balance	98,184
Life Sciences
Finite-lived Intangible Assets [Roll Forward]
Beginning Balance	93,226
Amortization	(12,713)
Currency impacts	0
Intangible assets acquired in acquisition	169,917
Measurement period adjustments	(700)
Ending balance	$ 249,730

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.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6388964&loc=d3e16225-109274

Reference 2: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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