Other - Net, (Income) Expense (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Nonoperating Income (Expense) [Abstract]
Interest expense	$ 400.6	$ 242.5	$ 225.0
Interest income	(80.4)	(159.3)	(166.4)
Debt extinguishment loss (Note 11)	252.5	0.0	0.0
Gain on sale of antibiotic business in China (Note 3)	(309.8)	0.0	0.0
Retirement benefit	(209.9)	(240.5)	(249.0)
Other (income) expense	(344.6)	11.7	(111.1)
Other–net, (income) expense	$ (291.6)	$ (145.6)	$ (301.5)

Amount before tax of gain (loss) recognized on the sale or disposal of a disposal group. Excludes discontinued operations.

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Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

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Amount of the cost of borrowed funds accounted for as interest expense.

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Amount of expense (reversal of expense) for net periodic benefit cost components, excluding service cost component, of defined benefit plan. Amount includes, but is not limited to, interest cost, expected (return) loss on plan asset, amortization of prior service cost (credit), amortization of (gain) loss, amortization of transition (asset) obligation, settlement (gain) loss, curtailment (gain) loss and certain termination benefits.

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