Commitments and Contingencies	12 Months Ended
Dec. 31, 2020
Commitments And Contingencies Disclosure [Abstract]
Commitments and Contingencies	13. Commitments and Contingencies Operating 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 former principal research and office space located at One Kendall Square in Cambridge, Massachusetts, which expired in June 2019. Total rent expense, net of rental income received from subleases, was less than $0.1 million for the year ended December 31, 2019.

The entire disclosure for commitments and contingencies.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-URI http://asc.fasb.org/topic&trid=2127136

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 440
-URI http://asc.fasb.org/topic&trid=2144648

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 440
-SubTopic 10
-Section 50
-Paragraph 4
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 440
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=121559207&loc=d3e25336-109308

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