Goodwill - Changes in Carrying Amount of Goodwill (Detail) - USD ($)	3 Months Ended	9 Months Ended
Dec. 31, 2018	Sep. 30, 2019
Goodwill [Roll Forward]
Beginning Balance		$ 439,452,000
Currency impacts/Other		(2,172,000)
Ending Balance	$ 439,452,000	437,280,000
Mobile Solutions
Goodwill [Roll Forward]
Ending Balance		0
Power Solutions
Goodwill [Roll Forward]
Beginning Balance		94,505,000
Currency impacts/Other		(202,000)
Ending Balance	94,505,000	94,303,000
Goodwill, impairment loss	109,100,000	0
Life Sciences
Goodwill [Roll Forward]
Beginning Balance		344,947,000
Currency impacts/Other		(1,970,000)
Ending Balance	$ 344,947,000	$ 342,977,000

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.

+ References

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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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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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