Product Sales - Schedule of Net Product Sales (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2022	Mar. 31, 2021
Disaggregation of Revenue [Line Items]
Revenues	$ 2,965.1	$ 2,528.7
UNITED STATES
Disaggregation of Revenue [Line Items]
Revenues	1,638.6	1,724.3
UNITED STATES \| EYLEA
Disaggregation of Revenue [Line Items]
Revenues	1,517.6	1,347.0
UNITED STATES \| Libtayo
Disaggregation of Revenue [Line Items]
Revenues	78.9	69.1
UNITED STATES \| Praluent
Disaggregation of Revenue [Line Items]
Revenues	33.6	43.3
UNITED STATES \| REGEN-COV
Disaggregation of Revenue [Line Items]
Revenues	0.0	262.2
UNITED STATES \| Evkeeza
Disaggregation of Revenue [Line Items]
Revenues	8.5	0.5
UNITED STATES \| ARCALYST
Disaggregation of Revenue [Line Items]
Revenues	$ 0.0	$ 2.2

Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

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+ Details