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Revenues - Narrative (Details) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2021 USD ($) wholesaler	Sep. 30, 2020 USD ($)	Sep. 30, 2021 USD ($) wholesaler	Sep. 30, 2020 USD ($)
Disaggregation of Revenue [Line Items]
Other Revenues	$ 2,778.9	$ 3,376.1	$ 8,247.9	$ 10,592.0
Number of wholesalers | wholesaler	2		2
Distributor One
Disaggregation of Revenue [Line Items]
Percentage of revenues from major distributors	26.90%	31.20%	29.10%	30.90%
Distributor Two
Disaggregation of Revenue [Line Items]
Percentage of revenues from major distributors	10.80%	15.60%	10.00%	16.00%
Other corporate revenues
Disaggregation of Revenue [Line Items]
Other Revenues	$ 143.8	$ 110.0	$ 314.1	$ 599.5
Other
Disaggregation of Revenue [Line Items]
Other Revenues	$ 157.8	$ 125.7	$ 350.1	$ 642.6

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Number of Wholesalers

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Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

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