Amount of stock and warrants issued during period as a result of a private placement agreement.

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- Definition

Value of stock and warrants issued as a result of a private placement agreement.

+ References

No definition available.

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- Definition

This element represents the amount of recognized equity-based compensation during the period, that is, the amount recognized as expense in the income statement (or as asset if compensation is capitalized). Alternate captions include the words "stock-based compensation".

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- Definition

Amount of increase in additional paid in capital (APIC) resulting from the issuance of warrants. Includes allocation of proceeds of debt securities issued with detachable stock purchase warrants.

+ References

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- Definition

Amount of a favorable spread to a debt holder between the amount of debt being converted and the value of the securities received upon conversion. This is an embedded conversion feature of convertible debt issued that is in-the-money at the commitment date.

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- Definition

The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest.

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- Definition

Number of shares issued which are neither cancelled nor held in the treasury.

+ References

No definition available.

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- Definition

Total of all stockholders' equity (deficit) items, net of receivables from officers, directors, owners, and affiliates of the entity which are attributable to the parent. The amount of the economic entity's stockholders' equity attributable to the parent excludes the amount of stockholders' equity which is allocable to that ownership interest in subsidiary equity which is not attributable to the parent (noncontrolling interest, minority interest). This excludes temporary equity and is sometimes called permanent equity.

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Number of shares issued during the period as a result of an employee stock purchase plan.

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- Definition

Number of new stock issued during the period.

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Number of shares of stock issued during the period that is attributable to transactions involving issuance of stock not separately disclosed.

+ References

No definition available.

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Number of share options (or share units) exercised during the current period.

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Aggregate change in value for stock issued during the period as a result of employee stock purchase plan.

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Equity impact of the value of new stock issued during the period. Includes shares issued in an initial public offering or a secondary public offering.

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Value of shares of stock issued during the period that is attributable to transactions involving issuance of stock not separately disclosed.

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No definition available.

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Value of stock issued as a result of the exercise of stock options.

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Statements of Stockholders' Equity (USD $) In Thousands, except Share data	Private Placement [Member] Common Stock [Member]	Private Placement [Member] Additional Paid-in Capital [Member]	Private Placement [Member]	Note Warrant [Member] Common Stock [Member]	Note Warrant [Member] Additional Paid-in Capital [Member]	Note Warrant [Member]	Common Stock [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member]	Total
Balance at Dec. 31, 2011							$ 100	$ 175,891	$ (160,239)	$ 15,752us-gaap_StockholdersEquity
Balance (in Shares) at Dec. 31, 2011							10,002,000
Issuance of stock, value	51	50,440	50,491	1	(1)
Issuance of stock, shares (in Shares)	5,100,000			5,000
Stock-based compensation expense								5,552		5,552
Fair value of warrants issued to non-employees								180		180
Net loss									(23,348)	(23,348)us-gaap_ProfitLoss
Conversion benefit included in Convertible Notes issued								3,169		3,169
Issuance of common stock under Employee Stock Purchase Plan								22		22
Issuance of common stock under Employee Stock Purchase Plan (in Shares)							4,000
Issuance of common stock upon exercise of stock options (in Shares)										0
Balance at Dec. 31, 2012							152	235,253	(183,587)	51,818us-gaap_StockholdersEquity
Balance (in Shares) at Dec. 31, 2012							15,111,000
Issuance of stock, value				2	598	600
Issuance of stock, shares (in Shares)				212,000
Stock-based compensation expense								10,890		10,890
Net loss									(55,283)	(55,283)us-gaap_ProfitLoss
Issuance of common stock in a public offering, net							77	57,725		57,802
Issuance of common stock in a public offering, net (in Shares)							7,706,000
Conversion benefit included in Convertible Notes issued								291		291
Issuance of common stock under Employee Stock Purchase Plan							1	33		34
Issuance of common stock under Employee Stock Purchase Plan (in Shares)							6,000
Issuance of common stock upon exercise of stock options							5	2,788		2,793
Issuance of common stock upon exercise of stock options (in Shares)							537,000			537,029
Balance at Dec. 31, 2013							237	307,578	(238,870)	68,945us-gaap_StockholdersEquity
Balance (in Shares) at Dec. 31, 2013							23,572,000
Issuance of stock, value				3	(3)
Issuance of stock, shares (in Shares)				304,000
Stock-based compensation expense								8,067		8,067
Net loss									(76,367)	(76,367)us-gaap_ProfitLoss
Issuance of common stock and pre-funded warrants in a public offering, net							47	58,869		58,916
Issuance of common stock and pre-funded warrants in a public offering, net (in Shares)							4,751,000
Conversion benefit included in Convertible Notes issued								309		309
Issuance of common stock under Employee Stock Purchase Plan								91		91
Issuance of common stock under Employee Stock Purchase Plan (in Shares)							12,000
Issuance of common stock upon exercise of stock options							5	3,096		3,101
Issuance of common stock upon exercise of stock options (in Shares)							588,000			756,593
Balance at Dec. 31, 2014							$ 292	$ 378,007	$ (315,237)	$ 63,062us-gaap_StockholdersEquity
Balance (in Shares) at Dec. 31, 2014							29,227,000