Leases - Additional Information (Details)							3 Months Ended	9 Months Ended
	Apr. 22, 2021 USD ($) ft²	Dec. 15, 2020 USD ($) ft²	Jun. 01, 2020 USD ($)	Apr. 13, 2020 USD ($) ft²	Oct. 15, 2019 USD ($) ft²	Mar. 12, 2019 USD ($) ft²	Sep. 30, 2021 USD ($)	Sep. 30, 2021 USD ($)	Dec. 31, 2020 USD ($)	Jan. 30, 2018 USD ($) ft²
Land Subject to Ground Leases | ft²	9,800					1,038
Operating Lease Monthly Rental Payment			$ 10,000			$ 2,000
Operating lease rental expenses							$ 0	$ 5,000
Lease obligation							5,418,000	5,418,000
Boston, MA
Security Deposit							100,000	$ 100,000	$ 100,000
Sublease term amendment	Aug. 31, 2021							Aug. 31, 2021
Operating lease expiration month and year								2016-08
Lessee Operating Lease Monthly Rental Payment	$ 26,000
Houston, TX
Land Subject to Ground Leases | ft²		35,482			8,443
Operating Lease Area | ft²				5,584						210
Operating Leases Future Minimum Monthly Payment Due Through Year 2021		$ 37,000		$ 12,000	$ 17,000					$ 1,000
Annual Base Rent		3.00%		3.00%	3.00%
Lessee Operating Lease Monthly Rental Payment			$ 15,000
Lease obligation							$ 0	$ 0