Commitments and Contingencies - Additional Information (Details) - USD ($)	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019	Dec. 31, 2019	Mar. 31, 2019
Other Commitments [Line Items]
Operating lease term	4 years		4 years
Operating leases, rent expense	$ 100,000	$ 100,000	$ 300,000	$ 200,000
Charleroi, Belgium
Other Commitments [Line Items]
Lease expiration date			Dec. 31, 2021
Operating lease, Hand serving to secure lease obligation	$ 66,000,000		$ 66,000,000		$ 66,000,000
Cambridge, Massachusetts
Other Commitments [Line Items]
Lease expiration date			May 31, 2022
Operating lease, Letter of credit to secure lease obligation						$ 57,000,000
Contract Termination
Other Commitments [Line Items]
Restructuring charges			$ 0		$ 0
Minimum
Other Commitments [Line Items]
Contractual Agreement Cancelation Notice period			30 days
Maximum
Other Commitments [Line Items]
Contractual Agreement Cancelation Notice period			60 days