Common Stock Voting Rights Votes

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- Definition

Aggregate number of common shares reserved for future issuance.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.29)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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Cash received on stock transaction after deduction of issuance costs.

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- Definition

The number of shares issued or sold by the subsidiary or equity method investee per stock transaction.

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Per share amount received by subsidiary or equity investee for each share of common stock issued or sold in the stock transaction.

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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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Number of equity instruments other than options outstanding, including both vested and non-vested instruments.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(i)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(ii)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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- Definition

Number of options outstanding, including both vested and non-vested options.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(i)-(ii)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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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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Common Stock and Stockholders' Equity (Details 1) $ / shares in Units, $ in Millions	1 Months Ended
	Jul. 31, 2017 USD ($) $ / shares shares	Dec. 31, 2017 vote shares	Dec. 31, 2016 shares	Dec. 31, 2015 shares	Dec. 31, 2014 shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock voting rights per share (vote) \| vote		1
Common stock options outstanding (in shares)		10,648,523	8,931,000
Total common shares reserved for future issuance (in shares)		13,430,899
Public Offering
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares issued	50,600,000
Sale of stock (usd per share) \| $ / shares	$ 0.91
Consideration received \| $	$ 43.0
Common stock available for future grant under the 2012 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock units outstanding		649,590
Inducement Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock units outstanding		41,948
Common stock available for future purchase under the 2012 Employee Stock Purchase Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock units outstanding		1,675,110
Common stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares outstanding (in shares)		103,955,147	52,924,805	52,669,266	48,944,530
Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Outstanding, Number		415,728