Goodwill and Other Intangibles - Finite and Indefinite-Lived Intangible Assets (Detail) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Finite-lived intangible assets
Gross Carrying Amount	$ 22,684	$ 23,274
Accumulated Amortization	(13,591)	(13,254)
Indefinite-lived intangible assets Goodwill	15,867	16,544
Patents [Member]
Finite-lived intangible assets
Gross Carrying Amount	4,806	4,806
Accumulated Amortization	(4,802)	(4,791)
Land Use Rights [Member]
Finite-lived intangible assets
Gross Carrying Amount	1,151	1,199
Accumulated Amortization	(203)	(201)
Trademarks [Member]
Finite-lived intangible assets
Gross Carrying Amount	1,716	1,770
Accumulated Amortization	(1,190)	(1,166)
Technology [Member]
Finite-lived intangible assets
Gross Carrying Amount	3,027	3,149
Accumulated Amortization	(1,263)	(1,215)
Customer Relationships [Member]
Finite-lived intangible assets
Gross Carrying Amount	11,984	12,350
Accumulated Amortization	$ (6,133)	$ (5,881)

Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
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-Section 50
-Paragraph 2
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- Definition

Amount before amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 928
-SubTopic 340
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- Definition

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.

+ References

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-Publisher FASB
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