Leases	9 Months Ended
Sep. 30, 2019
Leases [Abstract]
Leases	3. Leases The Company adopted the new leasing standards on January 1, 2019, using the modified retrospective transition method, which does not require restatement of prior periods, for all the leases existing as of the adoption date. The adoption of the new leasing standards did not have a significant impact on the Company’s consolidated financial statements. As of January 1, 2019, the Company’s only existing lease was the lease of its principal research and office space located at One Kendall Square in Cambridge, Massachusetts, which expired in June 2019.

The entire disclosure for operating leases of lessee. Includes, but is not limited to, description of operating lease and maturity analysis of operating lease liability.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-URI http://asc.fasb.org/subtopic&trid=77888251

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