Goodwill and Other Intangibles - Finite and Indefinite-Lived Intangible Assets (Detail) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Finite-lived intangible assets
Gross Carrying Amount	$ 22,445	$ 23,274
Accumulated Amortization	(13,987)	(13,254)
Indefinite-lived intangible assets Goodwill	15,621	16,544	$ 15,769
Patents [Member]
Finite-lived intangible assets
Gross Carrying Amount	4,806	4,806
Accumulated Amortization	(4,788)	(4,791)
Land Use Rights [Member]
Finite-lived intangible assets
Gross Carrying Amount	1,134	1,199
Accumulated Amortization	(203)	(201)
Trademark [Member]
Finite-lived intangible assets
Gross Carrying Amount	1,707	1,770
Accumulated Amortization	(1,247)	(1,166)
Technology [Member]
Finite-lived intangible assets
Gross Carrying Amount	2,994	3,149
Accumulated Amortization	(1,334)	(1,215)
Customer Relationships [Member]
Finite-lived intangible assets
Gross Carrying Amount	11,804	12,350
Accumulated Amortization	$ (6,415)	$ (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
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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
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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.

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-Publisher FASB
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