Related Party Transactions - Additional Information (Details) - One Of The Founders - USD ($)	3 Months Ended
Mar. 31, 2018	Mar. 31, 2017
Related Party Transaction [Line Items]
Annual consulting fees to company founder	$ 50,000
Consulting fees	0	$ 0
Outstanding liability to related party	$ 0	$ 0
Stock Option
Related Party Transaction [Line Items]
Shares issued to related party converted into stock options	13,852
Unvested Restricted Common Stock
Related Party Transaction [Line Items]
Shares issued to related party converted into restricted stock awards	43,290

Annual consulting fees to company founder.

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- Definition

Milestone contingent shares issued to non employee converted into restricted stock swards.

+ References

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- Definition

Milestone contingent shares issued to non employee converted into stock options.

+ References

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- Definition

Carrying amount as of the balance sheet date of obligations due all related parties.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 850
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39549-107864

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(k)(1))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
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-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 210
-Section S99
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Amount of cash outflow for fees classified as other.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 25
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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.

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