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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

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- Definition 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. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 730 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org//1943274/2147482916/730-10-50-1 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 912 -SubTopic 730 -Name Accounting Standards Codification -Section 25 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org//1943274/2147482517/912-730-25-1 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 985 -SubTopic 20 -Section 50 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org//1943274/2147481283/985-20-50-1 + Details
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