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Revenues - Narrative (Details) $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2020 USD ($)	Sep. 30, 2020 USD ($)	Jun. 30, 2020 USD ($)	Mar. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)	Sep. 30, 2019 USD ($)	Jun. 30, 2019 USD ($)	Mar. 31, 2019 USD ($)	Dec. 31, 2020 USD ($) wholesaler	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)
Disaggregation of Revenue [Line Items]
Number of wholesalers | wholesaler									2
Percentage of total revenues									14.70%	15.90%	14.70%
Revenues	$ 2,852.6	$ 3,376.1	$ 3,681.6	$ 3,534.3	$ 3,671.3	$ 3,600.1	$ 3,616.7	$ 3,489.8	$ 13,444.6	$ 14,377.9	$ 13,452.9
Other
Disaggregation of Revenue [Line Items]
Revenues	132.0	$ 125.7	407.6	$ 109.3	$ 145.7	$ 109.6	$ 160.0	$ 292.4	774.6	707.7	585.9
Other corporate
Disaggregation of Revenue [Line Items]
Revenues									719.1	584.5	459.4
Remaining performance obligation, amount	$ 153.8		$ 500.0						153.8
Bioverativ | Other
Disaggregation of Revenue [Line Items]
Revenues									48.6	$ 383.2	$ 206.7
Contract Manufacturing Customer | Other corporate
Disaggregation of Revenue [Line Items]
Revenues									$ 346.2
Distributor One
Disaggregation of Revenue [Line Items]
Percentage of revenue from major distributors									30.50%	30.00%	32.00%
Percentage receivables of wholesale distributor accounted in consolidated receivables	21.10%				24.10%				21.10%	24.10%
Distributor Two
Disaggregation of Revenue [Line Items]
Percentage of revenue from major distributors									15.30%	17.20%	18.40%
Percentage receivables of wholesale distributor accounted in consolidated receivables	8.50%				13.90%				8.50%	13.90%

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