Goodwill and Intangible Assets, Net - Components of Intangible Assets (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017
Finite-Lived Intangible Assets, Net [Abstract]
Gross	$ 62,924	$ 61,766
Accumulated amortization	(38,554)	(32,725)
Intangible assets, net	24,370	29,041
Gross value of fully amortized intangible assets	$ 7,100	6,000
Minimum
Finite-Lived Intangible Assets, Net [Abstract]
Estimated useful life of intangible assets	1 year
Maximum
Finite-Lived Intangible Assets, Net [Abstract]
Estimated useful life of intangible assets	15 years
Distribution rights (10 years)
Finite-Lived Intangible Assets, Net [Abstract]
Gross	$ 329	344
Accumulated amortization	(188)	(165)
Intangible assets, net	$ 141	179
Estimated useful life of intangible assets	10 years
Patents (10 years)
Finite-Lived Intangible Assets, Net [Abstract]
Gross	$ 14,560	13,250
Accumulated amortization	(5,704)	(5,310)
Intangible assets, net	$ 8,856	7,940
Estimated useful life of intangible assets	10 years
Trademark and trade names
Finite-Lived Intangible Assets, Net [Abstract]
Gross	$ 2,786	2,786
Accumulated amortization	(1,900)	(1,594)
Intangible assets, net	$ 886	1,192
Estimated useful life of intangible assets	10 years
Developed and core technology (5-15 years)
Finite-Lived Intangible Assets, Net [Abstract]
Gross	$ 12,560	12,560
Accumulated amortization	(8,087)	(6,071)
Intangible assets, net	$ 4,473	6,489
Developed and core technology (5-15 years) \| Minimum
Finite-Lived Intangible Assets, Net [Abstract]
Estimated useful life of intangible assets	5 years
Developed and core technology (5-15 years) \| Maximum
Finite-Lived Intangible Assets, Net [Abstract]
Estimated useful life of intangible assets	15 years
Capitalized software development costs (2 years)
Finite-Lived Intangible Assets, Net [Abstract]
Gross	$ 155	142
Accumulated amortization	0	(77)
Intangible assets, net	$ 155	65
Estimated useful life of intangible assets	2 years
Customer relationships
Finite-Lived Intangible Assets, Net [Abstract]
Gross	$ 32,534	32,534
Accumulated amortization	(22,675)	(19,395)
Intangible assets, net	$ 9,859	13,139
Customer relationships \| Minimum
Finite-Lived Intangible Assets, Net [Abstract]
Estimated useful life of intangible assets	10 years
Customer relationships \| Maximum
Finite-Lived Intangible Assets, Net [Abstract]
Estimated useful life of intangible assets	15 years
Order backlog
Finite-Lived Intangible Assets, Net [Abstract]
Gross	$ 0	150
Accumulated amortization	0	(113)
Intangible assets, net	$ 0	$ 37
Estimated useful life of intangible assets	1 year

Finite-Lived Intangible Assets, Fully Amortized, Gross

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- Definition

Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-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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-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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Amount after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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