Exercise price per share or per unit of warrants or rights outstanding.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 235

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.4-08.(i)(4))

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- Definition

The cash outflow for cost incurred directly with the issuance of an equity security.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Financing Activities

-URI http://asc.fasb.org/extlink&oid=6513228

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

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Price of a single share of a number of saleable stocks of a company.

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No definition available.

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Statements of Convertible Preferred Stock and Stockholders' (Deficit) Equity Parenthetical (USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2012	Dec. 31, 2013
Common stock [Member]
Share price (in USD per share)	$ 12
Stock issuance costs	$ 7,100
Warrant exercise price (in USD per share)	$ 12
Series B convertible preferred stock [Member]
Share price (in USD per share)		$ 9.41	$ 9.41
Stock issuance costs		10
Series C convertible preferred stock [Member]
Share price (in USD per share)			$ 8.18
Stock issuance costs			$ 251