The percentage of direct holding of company's common stock.

No definition available.

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- Definition

Number of company's directors and executive officers are affiliated .

+ References

No definition available.

+ Details

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- Definition

The number of stockholders reimbursed by the entity for shared office space and office related expenses.

+ References

No definition available.

+ Details

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- Definition

Number of warrants issued on purchase of one common stock.

+ References

No definition available.

+ Details

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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

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.

+ Details

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- Definition

Amount of selling, general and administrative expenses resulting from transactions, excluding transactions that are eliminated in consolidated or combined financial statements, with related party.

+ References

No definition available.

+ Details

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Balance Type:	debit
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- Definition

Per share or per unit amount of equity securities issued.

+ References

No definition available.

+ Details

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- Definition

Number of new stock issued during the period.

+ 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

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21463-112644

Reference 3: 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(28))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

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Period Type:	duration

- Details

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- Details

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- Details

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Period Type:

- Details

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- Details

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- Details

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Related Party Transactions (Details) $ / shares in Units, $ in Thousands		12 Months Ended
	Nov. 14, 2017 item $ / shares shares	Dec. 31, 2017 shares	Dec. 31, 2016 USD ($) shareholder
Private placement
Related Party Transactions
Number of warrants issued per common stock \| shares	1
Private placement \| HCV IX and Eli Lilly
Related Party Transactions
Number of affiliated directors and executive officers \| item	3
Private placement \| HCV IX and Eli Lilly \| Minimum
Related Party Transactions
Direct holding percentage	5.00%
Common Stock \| Private placement
Related Party Transactions
Issuance of stock (in shares) \| shares	2,958,094	2,958,094
Price per share (in dollars per share) \| $ / shares	$ 6.085
Warrant Liability \| Private placement
Related Party Transactions
Exercise price of warrant \| $ / shares	$ 6.085
Stockholder \| Shared office space and office related expenses
Related Party Transactions
Number of stockholders \| shareholder			1
Cost incurred to related party \| $			$ 308