Goodwill and Other Intangibles - Finite and Indefinite-Lived Intangible Assets (Detail) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Finite-lived intangible assets
Gross Carrying Amount	$ 30,041	$ 22,445
Accumulated Amortization	(14,825)	(13,987)
Indefinite-lived intangible assets Goodwill	25,278	15,621
Patents [Member]
Finite-lived intangible assets
Gross Carrying Amount	4,806	4,806
Accumulated Amortization	(4,806)	(4,788)
Land Use Rights [Member]
Finite-lived intangible assets
Gross Carrying Amount	1,124	1,134
Accumulated Amortization	(258)	(203)
Trademarks [Member]
Finite-lived intangible assets
Gross Carrying Amount	1,672	1,707
Accumulated Amortization	(1,294)	(1,247)
Technology [Member]
Finite-lived intangible assets
Gross Carrying Amount	6,767	2,994
Accumulated Amortization	(1,539)	(1,334)
Customer Relationships [Member]
Finite-lived intangible assets
Gross Carrying Amount	15,672	11,804
Accumulated Amortization	$ (6,928)	$ (6,415)

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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 928
-SubTopic 340
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6473545&loc=d3e61844-108004

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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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 5
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