Amount of litigation settlement payment in dispute one.

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Amount of foregone cash payment accumulated.

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The number of patents owned by the reporting entity.

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- Definition

Represents the percent of the consideration the Company receives from each disposition for the purpose of a compensation.

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- Definition

The number of days to plaintiff appeal period

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- Definition

The amount the company has agreed to pay in full towards reasonable and documented expenses.

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No definition available.

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Number of years upon which Company's obligation to compensate named party upon dispositions of undeveloped assets.

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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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Amount awarded to other party in judgment or settlement of litigation.

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- Definition

Reflects the estimated amount of loss from the specified contingency as of the balance sheet date.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=82911808&loc=d3e14435-108349

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The total number of new claims filed pertaining to a loss contingency during the period.

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- Definition

The cash inflow from issuance of preferred stocks identified as being convertible into another form of financial instrument, typically the entity's common stock.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section 45
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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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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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-Section 50
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-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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Commitments and Contingencies (Details)					9 Months Ended	12 Months Ended
Commitments and Contingencies (Details)	Feb. 09, 2018 USD ($)	Nov. 02, 2017 USD ($) shares	May 03, 2017 USD ($) shares	Jun. 09, 2016 item	Mar. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Oct. 22, 2015 patent
Guarantor Obligations [Line Items]
Plaintiff appeal period					45 days
VenBio Action
Guarantor Obligations [Line Items]
Reimbursement expense						$ 4,900,000
Settlement amount	$ 3,400,000
Greenhill Agreements \| Maximum
Guarantor Obligations [Line Items]
Reimbursement expense					$ 200,000
Goldenberg Sullivan And Markison \| Greenhill Agreements \| Convertible preferred stock
Guarantor Obligations [Line Items]
Proceeds from Issuance of Convertible Preferred Stock		$ 125,000,000
Employment Agreement \| Goldenberg Agreement
Guarantor Obligations [Line Items]
Total foregoing cash payments		2,400,000	$ 2,400,000
Litigation Settlement Payment In Dispute One		1,800,000	$ 1,800,000
Restricted stock units granted \| shares			1,500,000
Employment Agreement \| Goldenberg Agreement \| Minimum
Guarantor Obligations [Line Items]
Percentage Of Consideration Received From Dispositions			20.00%
Employment Agreement \| Goldenberg Agreement \| Maximum
Guarantor Obligations [Line Items]
Term Of Compensation Contract Upon Dispositions Of Undeveloped Assets			3 years
Employment Agreement \| Sullivan Agreement
Guarantor Obligations [Line Items]
Total foregoing cash payments		3,100,000	$ 3,100,000
Litigation Settlement Payment In Dispute One		900,000	900,000
Employment Agreement \| Goldenberg and Sullivan
Guarantor Obligations [Line Items]
Arbitration costs incurred					106,053
Employment Agreement \| Goldenberg and Sullivan \| Maximum
Guarantor Obligations [Line Items]
Arbitration costs incurred		$ 650,000	$ 650,000		$ 650,000
Employment Agreement \| Restricted Units Vesting Based on Certain Market Conditions \| Goldenberg Agreement
Guarantor Obligations [Line Items]
Restricted stock units granted \| shares		1,500,000
Patent litigation
Guarantor Obligations [Line Items]
Number of patents owned \| patent							3
Stockholder Federal Securities Cases
Guarantor Obligations [Line Items]
Number of purported class action cases filed \| item				2