Derivatives used in net investment hedge, net of tax, excluded component increase (decrease)

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Equity Method Investment, Ownership Percentage Before Additional Purchase Transaction

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Amount of net unrealized gain (loss) related to the change in fair value of foreign currency exchange rate derivatives designated as cash flow hedging instruments. Recorded in accumulated other comprehensive income to the extent that the cash flow hedge is determined to be effective.

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Unrealized Gross Gains on Foreign Currency Derivatives, Net, before Tax

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Unrealized Gross Losses on Foreign Currency Derivatives, Net, before Tax

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Amount, after tax, of accumulated gain (loss) from increase (decrease) in value of excluded component of derivative hedge.

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Contractual interest rate for funds borrowed, under the debt agreement.

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Fair value, before effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets elected not to be offset. Excludes assets not subject to a master netting arrangement.

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The portion of gains and losses (net) on derivative instruments designated and qualifying as hedging instruments representing (a) the amount of the hedge ineffectiveness and (b) the amount, if any, excluded from the assessment of hedge effectiveness.

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Nominal or face amount used to calculate payment on derivative.

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Period remaining until the derivative contract matures, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Period the derivative contract is outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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Amount of unrealized loss on investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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Aggregate net gain (loss) on all derivative instruments recognized in earnings during the period, before tax effects.

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Amount of gain (loss) recognized in earnings in the period from the increase (decrease) in fair value of foreign currency derivatives not designated as hedging instruments.

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Amount, before tax, of reclassification of gain (loss) from accumulated other comprehensive income (AOCI) for derivative instrument designated and qualifying as cash flow hedge included in assessment of hedge effectiveness.

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The cash outflow associated with the purchase of or advances to an equity method investments, which are investments in joint ventures and entities in which the entity has an equity ownership interest normally of 20 to 50 percent and exercises significant influence.

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Amount of increase (decrease) in the cumulative translation adjustment from gain (loss), after tax, on foreign currency derivatives, that are designated as, and are effective as, economic hedges of a net investment in a foreign entity.

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Derivative Instruments (Details) $ in Millions, ₩ in Billions	1 Months Ended		3 Months Ended				9 Months Ended		12 Months Ended
	Nov. 30, 2018 USD ($)	Nov. 30, 2018 KRW (₩)	Sep. 30, 2021 USD ($)	Mar. 31, 2021 USD ($)	Sep. 30, 2020 USD ($)	Mar. 31, 2020 USD ($)	Sep. 30, 2021 USD ($)	Sep. 30, 2020 USD ($)	Dec. 31, 2020 USD ($)
Derivatives [Line Items]
Gain/Loss on fair value of foreign currency forward contracts			$ 21.9				$ 21.9		$ (212.5)
Gain (loss) on foreign currency derivative instruments not designated as hedging instruments			(13.5)		$ 7.8		(26.1)	$ 13.7
Unrealized Gross Losses on Foreign Currency Derivatives, Net, before Tax			38.4				38.4
Unrealized Gross Gains on Foreign Currency Derivatives, Net, before Tax			16.5				16.5
Gains (losses) on net investment hedges			15.1		(11.3)		35.2	5.5
Ionis, Sangamo, Denali and Sage
Derivatives [Line Items]
Net losses recognized on the decrease in fair value of equity securities							$ 709.1
Minimum
Derivatives [Line Items]
Range of durations of foreign currency forward contracts							1 month		1 month
Maximum
Derivatives [Line Items]
Range of durations of foreign currency forward contracts							18 months		24 months
Not designated as hedging instrument
Derivatives [Line Items]
Derivative, Notional Amount			1,400.6				$ 1,400.6		$ 1,158.0
Other current assets \| Designated as hedging instrument
Derivatives [Line Items]
Derivative asset, fair value			34.5				34.5		0.0
Other current assets \| Not designated as hedging instrument
Derivatives [Line Items]
Derivative asset, fair value			6.1				6.1		20.5
Other noncurrent assets \| Designated as hedging instrument
Derivatives [Line Items]
Derivative asset, fair value			14.1				14.1		0.0
Accrued expenses and other \| Designated as hedging instrument
Derivatives [Line Items]
Derivative liability, fair value			11.8				11.8		157.1
Accrued expenses and other \| Not designated as hedging instrument
Derivatives [Line Items]
Derivative liability, fair value			15.9				15.9		4.7
Foreign exchange contract \| Designated as hedging instrument
Derivatives [Line Items]
Derivative, Notional Amount			2,080.8				2,080.8		3,229.7
Interest rate swap \| Designated as hedging instrument
Derivatives [Line Items]
Derivative, Notional Amount			675.0				675.0
Cash Flow Hedging [Member] \| Foreign exchange contract \| Other long-term liabilities
Derivatives [Line Items]
Derivative liability, fair value			0.0				$ 0.0		35.7
Net Investment Hedging
Derivatives [Line Items]
Remaining duration of Net Investment Hedges							1 month
Unrealized gain (loss) on net investment hedges in AOCI				$ 21.2			$ 25.0
Derivative qualifying as net investment hedge, excluded component			0.0				0.0		0.2
Gains (losses) on net investment hedges			24.9		(10.4)		46.1	5.0
Gains (losses) on net investment hedge, excluded component			0.0		(0.2)		(1.1)	3.1
Net Investment Hedging \| Foreign exchange contract \| Other current assets
Derivatives [Line Items]
Derivative asset, fair value			25.3				25.3		0.0
Net Investment Hedging \| Foreign exchange contract \| Accrued expenses and other
Derivatives [Line Items]
Derivative liability, fair value			0.0				0.0		19.7
Interest Expense \| Interest rate swap
Derivatives [Line Items]
Gain on interest rate swap							3.3
Revenue \| Foreign exchange contract
Derivatives [Line Items]
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), Reclassification, before Tax			(14.9)		(9.1)		(68.7)	41.6
Revenue \| Cash flows, revenue \| Foreign exchange contract
Derivatives [Line Items]
Gain on interest rate swap			(0.7)		(8.7)		(4.5)	(1.0)
Operating expense \| Foreign exchange contract
Derivatives [Line Items]
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), Reclassification, before Tax			(0.3)		1.5		(0.3)	1.4
Operating expense \| Cash flows, operating expenses \| Foreign exchange contract
Derivatives [Line Items]
Gain on interest rate swap			0.0		0.4		(0.4)	(0.7)
Other income (expense) \| Net Investment Hedging
Derivatives [Line Items]
Gain (loss) recognized in net income, excluded component			0.0		$ 0.9		0.1	$ 2.6
Euro \| Foreign exchange contract \| Designated as hedging instrument
Derivatives [Line Items]
Derivative, Notional Amount			1,901.5				1,901.5		2,979.1
British pound \| Foreign exchange contract \| Designated as hedging instrument
Derivatives [Line Items]
Derivative, Notional Amount			30.1				30.1		0.0
Swiss franc \| Foreign exchange contract \| Designated as hedging instrument
Derivatives [Line Items]
Derivative, Notional Amount			63.6				63.6		250.6
Japan, Yen \| Foreign exchange contract \| Designated as hedging instrument
Derivatives [Line Items]
Derivative, Notional Amount			25.2				25.2		0.0
Canadian dollar \| Foreign exchange contract \| Designated as hedging instrument
Derivatives [Line Items]
Derivative, Notional Amount			$ 60.4				$ 60.4		$ 0.0
2.900% Senior Notes due 2020
Derivatives [Line Items]
Senior notes interest rate			2.90%				2.90%
Samsung Bioepis
Derivatives [Line Items]
Percentage of stake in entity					5.00%			5.00%
Equity Method Investment, Ownership Percentage			49.90%				49.90%
Payments to acquire additional investment in equity method investment	$ 676.6	₩ 759.5				$ 676.6
Short-term derivative
Derivatives [Line Items]
Gain/Loss on fair value of foreign currency forward contracts			$ 9.6				$ 9.6
Range of durations of foreign currency forward contracts							12 months