Fair Value Measurements - Summary of Changes in the Fair Value of the Liability (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Fair value adjustment of contingent consideration	$ (246)	$ 157	$ (536)
NLEX [Member] \| Contingent Consideration [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Beginning balance		2,774
Payment of contingent consideration		(2,618)
Fair value adjustment of contingent consideration		$ (157)

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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- Definition

Amount of purchases of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)
-URI http://asc.fasb.org/extlink&oid=99377789&loc=d3e19207-110258

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- Definition

Fair value of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=99377789&loc=d3e19207-110258

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- Definition

Amount of addition (reduction) to the amount at which a liability could be incurred (settled) in a current transaction between willing parties.

+ References

No definition available.

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