Goodwill and Intangible Assets, Net - Goodwill (Details) $ in Thousands	12 Months Ended
Dec. 31, 2016 USD ($) segment item	Dec. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)
Goodwill and Intangible Assets, Net
Number of operating segments \| segment	1
Number of reportable segments \| segment	1
Number of reporting units \| item	1
Changes in the carrying amount of goodwill
Goodwill, Beginning Balance	$ 10,781	$ 29,719
Acquisition-related goodwill		1,251
Impairment of goodwill	0	(20,890)	$ 0
Purchase price adjustment related to acquisition		651
Foreign exchange impact	(23)	50
Goodwill, Ending Balance	$ 10,758	$ 10,781	$ 29,719

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.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
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Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

+ References

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Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount of increase (decrease) from adjustments after acquisition date under purchase accounting of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Amount of increase (decrease) from foreign currency translation adjustments 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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- Definition

Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues.

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Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

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Number of reporting units tested for impairment of goodwill. A reporting unit is an operating segment or one level below an operating segment.

+ References

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