Discontinued Operations - Financial Results of Discontinued Operations (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2021	Sep. 30, 2021	Jun. 30, 2021	Mar. 31, 2021	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Cost and expenses:
Net (loss) income from discontinued operations	$ 3,957	$ (4,507)	$ (3,427)	$ 1,965,202	$ (13,116)	$ (19,804)	$ (8,983)	$ 43,838	$ 1,961,225	$ 1,935	$ (110,064)
Agios Oncology Business | Discontinued Operations, Disposed of by Sale
Revenues:
Total revenue									41,409	203,196	117,912
Cost and expenses:
Cost of sales									706	2,805	1,317
Research and development									41,564	146,659	196,632
Selling, general and administrative									8,551	33,965	30,027
Total cost and expenses									50,821	183,429	227,976
(Loss) income from discontinued operations									(9,412)	19,767	(110,064)
Net income (loss) from discontinued operations, net of tax									(5,697)	(17,832)	0
Gain on the sale of the oncology business									1,989,133	0
(Loss) income from discontinued operations, pre-tax									1,974,024	1,935	(110,064)
Income tax expense									(12,799)	0	0
Net (loss) income from discontinued operations									1,961,225	1,935	(110,064)
Agios Oncology Business | Product revenue, net | Discontinued Operations, Disposed of by Sale
Revenues:
Total revenue									36,909	121,089	59,851
Agios Oncology Business | Collaboration revenue – related party | Discontinued Operations, Disposed of by Sale
Revenues:
Total revenue									1,350	68,274	39,257
Agios Oncology Business | Collaboration revenue – other | Discontinued Operations, Disposed of by Sale
Revenues:
Total revenue									491	3,571	8,262
Agios Oncology Business | Royalty revenue – related party | Discontinued Operations, Disposed of by Sale
Revenues:
Total revenue									$ 2,659	$ 10,262	$ 10,542