Acquisitions - 2017 Acquisitions (Details) - Cogeon GmbH - USD ($) $ in Thousands	1 Months Ended	12 Months Ended
Oct. 31, 2017	Dec. 31, 2017
Business Acquisition [Line Items]
Total fair value of purchase consideration	$ 15,014
Escrow	$ 2,244
Escrow release period	24 months
Contingent consideration arrangements, range of outcomes, value, high	$ 9,000
Contingent purchase consideration, cash		$ 600
Acquisition related expenses		$ 700
Contingent Equity Grants
Business Acquisition [Line Items]
Contingent consideration arrangements, range of outcomes, value, high	$ 3,800

Business Combination, Consideration Transferred, Escrow

No definition available.

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- Definition

Business Combination, Consideration Transferred, Escrow Release Period

+ References

No definition available.

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- Definition

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.

+ References

No definition available.

+ Details

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- Definition

This element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 25
-Paragraph 23
-URI http://asc.fasb.org/extlink&oid=84229725&loc=d3e1043-128460

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- Definition

Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 30
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=6911251&loc=d3e6578-128477

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-Name Accounting Standards Codification
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-Section 50
-Paragraph 1
-Subparagraph (b)
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 30
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=6911251&loc=d3e6613-128477

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- Definition

For contingent consideration arrangements recognized in connection with a business combination, this element represents an estimate of the high-end of the potential range (undiscounted) of the consideration which may be paid.

+ References

+ Details

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- Definition

Amount of liability recognized arising from contingent consideration in a business combination.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
-Paragraph 1
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-Name Accounting Standards Codification
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-Paragraph 1
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-Name Accounting Standards Codification
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-SubTopic 30
-Section 25
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=6911189&loc=d3e6408-128476

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