Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section S99

-Paragraph 1

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-Section 50

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-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 14

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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.

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No definition available.

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- Definition

Unrecognized cost of unvested share-based compensation awards.

+ References

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-SubTopic 10

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- Definition

Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Stock‑Based Compensation (CompExp) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Stock based compensation expense
Stock based compensation expense	$ 1,592	$ 418
Cost of revenues
Stock based compensation expense
Stock based compensation expense	272	33
Research and development
Stock based compensation expense
Stock based compensation expense	320	97
Selling, general and administrative
Stock based compensation expense
Stock based compensation expense	1,000	288
Employee and non-employee stock options
Stock based compensation expense
Stock based compensation expense			$ 2,740	$ 3,028
Unrecognized compensation expense	14,800		$ 14,800
Unrecognized compensation expense recognized over weighted average period			2 years 1 month 13 days
Employee and non-employee stock options \| Cost of revenues
Stock based compensation expense
Stock based compensation expense			$ 355	101
Employee and non-employee stock options \| Research and development
Stock based compensation expense
Stock based compensation expense			581	1,150
Employee and non-employee stock options \| Selling, general and administrative
Stock based compensation expense
Stock based compensation expense			1,804	1,777
Employee stock options
Stock based compensation expense
Stock based compensation expense	1,323	408	2,418	3,004
Employee stock options \| Cost of revenues
Stock based compensation expense
Stock based compensation expense	88	32	149	97
Employee stock options \| Research and development
Stock based compensation expense
Stock based compensation expense	309	94	558	1,143
Employee stock options \| Selling, general and administrative
Stock based compensation expense
Stock based compensation expense	926	282	1,711	1,764
Non-employee stock options
Stock based compensation expense
Stock based compensation expense	269	10	322	24
Non-employee stock options \| Cost of revenues
Stock based compensation expense
Stock based compensation expense	184	1	206	4
Non-employee stock options \| Research and development
Stock based compensation expense
Stock based compensation expense	11	3	23	7
Non-employee stock options \| Selling, general and administrative
Stock based compensation expense
Stock based compensation expense	$ 74	$ 6	$ 93	$ 13