Share-Based Payments (Details) - USD ($) $ in Millions		3 Months Ended
Sep. 26, 2023	Mar. 31, 2024	Mar. 31, 2023
Share-based Compensation Expense included in consolidated statements of income
Share-based compensation expense		$ (76.1)	$ (78.9)
Subtotal		71.4	81.4
Capitalized share-based compensation costs		(3.3)	(3.3)
Share-based compensation expense included in total costs and expenses		68.1	78.1
Income tax effect		(12.9)	(14.7)
Selling, General and Administrative Expense		581.5	605.0
Reata Pharmaceuticals, Inc
Share-based Compensation Expense included in consolidated statements of income
Operating expenses	$ 393.4
Selling, General and Administrative Expense	196.4
Research and development expense asset acquired	$ 197.0
Research and development
Share-based Compensation Expense included in consolidated statements of income
Share-based compensation expense		27.4	31.3
Selling, general and administrative
Share-based Compensation Expense included in consolidated statements of income
Share-based compensation expense		44.0	50.1
Total share-based compensation expense, net of tax
Share-based Compensation Expense included in consolidated statements of income
Share-based compensation expense		$ 55.2	$ 63.4

Share based compensation expense included in costs and expenses.

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Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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Amount, after tax, of expense for award under share-based payment arrangement.

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Amount of cost capitalized for award under share-based payment arrangement.

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Amount of tax benefit for recognition of expense of award under share-based payment arrangement.

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Generally recurring costs associated with normal operations except for the portion of these expenses which can be clearly related to production and included in cost of sales or services. Includes selling, general and administrative expense.

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The aggregate costs incurred (1) in a planned search or critical investigation aimed at discovery of new knowledge with the hope that such knowledge will be useful in developing a new product or service, a new process or technique, or in bringing about a significant improvement to an existing product or process; or (2) to translate research findings or other knowledge into a plan or design for a new product or process or for a significant improvement to an existing product or process whether intended for sale or the entity's use, during the reporting period charged to research and development projects, including the costs of developing computer software up to the point in time of achieving technological feasibility, and costs allocated in accounting for a business combination to in-process projects deemed to have no alternative future use.

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The aggregate total costs related to selling a firm's product and services, as well as all other general and administrative expenses. Direct selling expenses (for example, credit, warranty, and advertising) are expenses that can be directly linked to the sale of specific products. Indirect selling expenses are expenses that cannot be directly linked to the sale of specific products, for example telephone expenses, Internet, and postal charges. General and administrative expenses include salaries of non-sales personnel, rent, utilities, communication, etc.

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