Segment Information - Geographic Information (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Revenue, Major Customer [Line Items]
Revenue	$ 9,675.9	$ 9,835.6	$ 10,173.4
Reportable Segment
Revenue, Major Customer [Line Items]
Revenue	9,675.9	9,835.6	10,173.4
Long-lived assets	3,537.7	3,729.7	3,702.5
U.S. | Reportable Segment
Revenue, Major Customer [Line Items]
Long-lived assets	1,366.1	1,443.0	1,369.4
Europe | Reportable Segment
Revenue, Major Customer [Line Items]
Long-lived assets	2,139.2	2,248.0	2,275.8
Germany | Reportable Segment
Revenue, Major Customer [Line Items]
Long-lived assets	13.3	17.5	21.0
Asia | Reportable Segment
Revenue, Major Customer [Line Items]
Long-lived assets	8.5	8.3	13.7
Other | Reportable Segment
Revenue, Major Customer [Line Items]
Long-lived assets	10.6	12.9	22.6
Product revenue, net
Revenue, Major Customer [Line Items]
Revenue	7,213.5	7,246.7	7,987.8
Product revenue, net | Reportable Segment
Revenue, Major Customer [Line Items]
Revenue	7,213.5	7,246.7	7,987.8
Product revenue, net | U.S.
Revenue, Major Customer [Line Items]
Revenue	3,237.3	3,141.4	3,469.3
Product revenue, net | U.S. | Reportable Segment
Revenue, Major Customer [Line Items]
Revenue	3,237.3	3,141.4	3,469.3
Product revenue, net | Europe | Reportable Segment
Revenue, Major Customer [Line Items]
Revenue	2,171.5	2,127.4	2,401.3
Product revenue, net | Germany | Reportable Segment
Revenue, Major Customer [Line Items]
Revenue	955.6	868.0	926.2
Product revenue, net | Asia | Reportable Segment
Revenue, Major Customer [Line Items]
Revenue	366.9	649.4	672.1
Product revenue, net | Other | Reportable Segment
Revenue, Major Customer [Line Items]
Revenue	482.2	460.5	518.9
Revenue from anti-CD20 therapeutic programs
Revenue, Major Customer [Line Items]
Revenue	1,749.9	1,689.6	1,700.5
Revenue from anti-CD20 therapeutic programs | Reportable Segment
Revenue, Major Customer [Line Items]
Revenue	1,749.9	1,689.6	1,700.5
Revenue from anti-CD20 therapeutic programs | U.S. | Reportable Segment
Revenue, Major Customer [Line Items]
Revenue	1,673.6	1,618.5	1,636.4
Revenue from anti-CD20 therapeutic programs | Europe | Reportable Segment
Revenue, Major Customer [Line Items]
Revenue	0.6	0.4	0.1
Revenue from anti-CD20 therapeutic programs | Germany | Reportable Segment
Revenue, Major Customer [Line Items]
Revenue	0.0	0.0	0.0
Revenue from anti-CD20 therapeutic programs | Asia | Reportable Segment
Revenue, Major Customer [Line Items]
Revenue	0.0	0.0	0.0
Revenue from anti-CD20 therapeutic programs | Other | Reportable Segment
Revenue, Major Customer [Line Items]
Revenue	75.7	70.7	64.0
Contract manufacturing, royalty and other revenue
Revenue, Major Customer [Line Items]
Revenue	652.6	899.3	485.1
Contract manufacturing, royalty and other revenue | Reportable Segment
Revenue, Major Customer [Line Items]
Revenue	652.6	899.3	485.1
Contract manufacturing, royalty and other revenue | U.S. | Reportable Segment
Revenue, Major Customer [Line Items]
Revenue	395.0	673.6	425.8
Contract manufacturing, royalty and other revenue | Europe | Reportable Segment
Revenue, Major Customer [Line Items]
Revenue	0.4	11.7	11.7
Contract manufacturing, royalty and other revenue | Germany | Reportable Segment
Revenue, Major Customer [Line Items]
Revenue	0.0	0.0	0.0
Contract manufacturing, royalty and other revenue | Asia | Reportable Segment
Revenue, Major Customer [Line Items]
Revenue	257.2	214.0	47.6
Contract manufacturing, royalty and other revenue | Other | Reportable Segment
Revenue, Major Customer [Line Items]
Revenue	$ 0.0	$ 0.0	$ 0.0