Common Stock Issued In Lieu Of Board Fees

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- Definition

Value of stock purchased by board.

+ References

No definition available.

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- Definition

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

+ References

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))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

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- Definition

Number of warrants or rights outstanding.

+ References

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))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

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- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=66011266&loc=d3e33918-111571

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- Definition

The cash inflow associated with the amount received from holders exercising their stock warrants.

+ References

No definition available.

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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.

+ References

No definition available.

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- Definition

Number of non-option equity instruments exercised by participants.

+ 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)(iv)(2)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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Related Party Transactions - Overview of Related Parties (Details) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Jan. 21, 2018
Related Party Transactions
Ownership percentage				48.40%
Number of Warrants	43,757,379	51,709,460
Exercise price of warrants	$ 0.24	$ 0.31
Common stock issued in lieu of board fees	62,939	101,239	40,934
Proceeds from issuance of common stock in lieu of director board and committee fees	$ 0.1	$ 0.2	$ 0.1
Common Stock \| Board of Director
Related Party Transactions
Ownership percentage	9.40%
Pillar I
Related Party Transactions
Number of warrants exercised		1,370,000
Proceeds from exercise of warrants		$ 2.0
Pillar II
Related Party Transactions
Number of warrants exercised	5,034,061		232,759
Proceeds from exercise of warrants	$ 3.5		$ 0.2
Pillar III
Related Party Transactions
Number of warrants exercised			2,600,000
Proceeds from exercise of warrants			$ 1.2
Pillar Investment Entities \| Common Stock
Related Party Transactions
Ownership percentage	13.10%
Besancon
Related Party Transactions
Number of warrants exercised	2,918,020
Proceeds from exercise of warrants	$ 1.9
Number of Warrants	1,200,000
Exercise price of warrants	$ 0.47
Baker Bros. Advisors LP
Related Party Transactions
Number of Warrants	20,316,327
Exercise price of warrants	$ 0.47
Baker Bros. Advisors LP \| Pre-funded Warrants
Related Party Transactions
Number of Warrants	22,151,052
Exercise price of warrants	$ 0.01