Asset Impairment, Restructuring, and Other Special Charges (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Business Acquisition [Line Items]
Severance	$ 9.8	$ (3.6)
Asset impairment and other special charges	50.1	427.5
Total asset impairment, restructuring, and other special charges	59.9	$ 423.9
Loxo Oncology, Inc.
Business Acquisition [Line Items]
Asset impairment and other special charges	$ 400.7

Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

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Amount of restructuring charges, remediation cost, and asset impairment loss.

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Amount of expenses for special or contractual termination benefits provided to current employees involuntarily terminated under a benefit arrangement associated exit or disposal activities pursuant to an authorized plan. Excludes expenses related to one-time termination benefits, a discontinued operation or an asset retirement obligation.

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