Commitments and Contingencies	12 Months Ended
Dec. 31, 2019
Commitments And Contingencies Disclosure [Abstract]
Commitments and Contingencies	14. 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 and $0.1 million for the years ended December 31, 2019 and 2018, respectively.

Commitments and Contingencies

12 Months Ended

Dec. 31, 2019

Commitments And Contingencies Disclosure [Abstract]

14. 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 and $0.1 million for the years ended December 31, 2019 and 2018, respectively.