Revenue Recognition - Disaggregation of Revenue (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Disaggregation of Revenue [Line Items]
Product revenues, net	$ 2,483.5	$ 2,334.3	$ 7,351.5	$ 6,628.0
United States
Disaggregation of Revenue [Line Items]
Product revenues, net	1,554.2	1,455.6	4,465.8	4,238.9
Total product revenues outside of the United States
Disaggregation of Revenue [Line Items]
Product revenues, net	929.3	878.7	2,885.7	2,389.1
Europe
Disaggregation of Revenue [Line Items]
Product revenues, net	766.5	730.5	2,373.7	2,018.3
Other
Disaggregation of Revenue [Line Items]
Product revenues, net	162.8	148.2	512.0	370.8
TRIKAFTA/KAFTRIO
Disaggregation of Revenue [Line Items]
Product revenues, net	2,274.3	2,010.5	6,611.4	5,665.3
KALYDECO
Disaggregation of Revenue [Line Items]
Product revenues, net	112.8	139.4	363.1	417.1
ORKAMBI
Disaggregation of Revenue [Line Items]
Product revenues, net	63.0	146.2	281.8	399.9
SYMDEKO/SYMKEVI
Disaggregation of Revenue [Line Items]
Product revenues, net	$ 33.4	$ 38.2	$ 95.2	$ 145.7