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Number of common shares held by the related party representing the voting power.

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Restriction on the beneficial ownership percentage to be held after the share issuable upon conversion or exercise of convertible securities.

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Represents number of written days of notice to be given to the company for increasing the beneficial ownership percentage restriction.

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Shares issued on exercise of warrants during period.

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- Definition

Value of stock purchased by board.

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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/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 3
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Number of securities into which the class of warrant or right may be converted. For example, but not limited to, 500,000 warrants may be converted into 1,000,000 shares.

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Number of warrants or rights outstanding.

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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.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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- Definition

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

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
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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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- Definition

Value, after value of shares used to satisfy grantee's tax withholding obligation for award under share-based payment arrangement, of restricted shares issued. Excludes cash used to satisfy grantee's tax withholding obligation.

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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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Number of non-option equity instruments exercised by participants.

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Related Party Transactions - Overview of Related Parties (Details) - USD ($) $ / shares in Units, $ in Millions	1 Months Ended		12 Months Ended
	Dec. 31, 2020	Jan. 31, 2020	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Related Party Transactions
Exercise price of warrants	$ 1.28		$ 1.28	$ 0.75
Number of Warrants	16,967,828		16,967,828	5,098,916
Common stock issued in lieu of board fees			145,392	53,985	13,654
Restricted stock units
Related Party Transactions
Award granted			365,845
Restricted stock units \| 2013 Stock Incentive Plan
Related Party Transactions
Award granted			128,170
Board of Director
Related Party Transactions
Ownership percentage	12.00%		12.00%
Aggregate common shares			4,608,786
Maximum
Related Party Transactions
Proceeds from issuance of common stock in lieu of director board and committee fees			$ 0.3	$ 0.1	$ 0.1
Baker Bros. Advisors LP
Related Party Transactions
Number of warrants exercised					2,700,791
Exercise price of warrants					$ 3.76
Proceeds from exercise of warrants					$ 9.5
Maximum beneficial ownership percentage holding, after convertible securities converted				4.99%
Prior notice period (in days)				61 days
Baker Bros. Advisors LP \| Maximum
Related Party Transactions
Maximum beneficial ownership percentage holding, after convertible securities converted				19.99%
Baker Bros. Advisors LP \| Pre-funded Warrants \| Scenario One
Related Party Transactions
Exercise price of warrants	$ 0.08		$ 0.08
Baker Bros. Advisors LP \| Pre-funded Warrants \| Scenario One \| Maximum
Related Party Transactions
Number of Warrants	2,708,812		2,708,812
Baker Bros. Advisors LP \| Pre-funded Warrants \| Scenario Two \| Maximum
Related Party Transactions
Number of Shares	2,368,400		2,368,400
Baker Bros. Advisors LP \| Series B1 Preferred Warrant \| Scenario Two
Related Party Transactions
Exercise price of warrants	$ 152		$ 152
Baker Bros. Advisors LP \| Preferred stock \| Scenario Two
Related Party Transactions
Exercise price of warrants	$ 1.52		$ 1.52
Number of Warrants	23,684		23,684
Pillar Investment Entities
Related Party Transactions
Ownership percentage	18.00%		18.00%
Pillar Investment Entities \| Pre-funded Warrants
Related Party Transactions
Exercise price of warrants		$ 0.01
Shares issued on exercise of warrants during the period		643,525
Pillar Investment Entities \| Common Stock Warrants Exercise Price, Two Point Two Eight
Related Party Transactions
Exercise price of warrants	$ 2.28		$ 2.28
Number of Shares	3,039,514		3,039,514
Pillar Investment Entities \| Common Stock Warrants Exercise Price Two Point Five Eight
Related Party Transactions
Exercise price of warrants	$ 2.58		$ 2.58
Number of Shares	2,764,227		2,764,227
Pillar Investment Entities \| Pre Funded Warrant, Tranche One
Related Party Transactions
Exercise price of warrants	$ 0.01		$ 0.01
Number of Shares	2,014,234		2,014,234
Pillar Investment Entities \| Common Stock Warrants Exercise Price Two Point Seven One
Related Party Transactions
Exercise price of warrants	$ 2.71		$ 2.71
Number of Shares	1,373,626		1,373,626
Pillar Investment Entities \| Pre Funded Warrant, Tranche Two
Related Party Transactions
Exercise price of warrants	$ 0.01		$ 0.01
Number of Shares	2,677,311		2,677,311
Besancon
Related Party Transactions
Exercise price of warrants					$ 3.76
Proceeds from exercise of warrants					$ 0.6
Shares issued on exercise of warrants during the period					150,000
Chief Executive Officer \| 2013 Stock Incentive Plan
Related Party Transactions
Award granted	128,170
Proceeds from issuance of restricted stock in lieu of salary	$ 0.6