Maximum target number of market stock units granted based on stock performance in percent.

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Minimum target number of market stock units granted based on stock performance in percent.

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Number of days for calculation of average closing stock price.

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Number of equal annual increments.

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Number of share-based compensation plans pursuant to which awards are currently being made.

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Ratio of total number of shares reserved under the plan.

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Weighted-average period to recognize the cost of nonvested awards.

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

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Amount of cost not yet recognized for nonvested 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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Amount of expense for research and development. Includes, but is not limited to, cost for computer software product to be sold, leased, or otherwise marketed and writeoff of research and development assets acquired in transaction other than business combination or joint venture formation or both. Excludes write-down of intangible asset acquired in business combination or from joint venture formation or both, used in research and development activity.

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Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480008/505-10-S99-1

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Share-Based Payments - Narrative (Details) $ / shares in Units, $ in Millions			1 Months Ended	3 Months Ended		12 Months Ended
	Jul. 02, 2024 USD ($)	Sep. 26, 2023 USD ($)	Jun. 30, 2024 shares	Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2025 USD ($) increment plan $ / shares shares	Dec. 31, 2024 USD ($) $ / shares	Dec. 31, 2023 USD ($) $ / shares	Dec. 31, 2022 USD ($) $ / shares shares
Share-based Compensation Arrangement by Share-based Payment Award
Selling, general and administrative						$ 2,433.6	$ 2,403.7	$ 2,549.7
Unrecognized compensation cost related to unvested share-based compensation						$ 292.6
Weighted-average period to recognize the cost of unvested awards (in years)						1 year 10 months 24 days
Granted (in shares) \| shares						0
Vesting period						3 years
Shares issued under ESPP (in shares) \| shares			2,500,000
Research and development
Share-based Compensation Arrangement by Share-based Payment Award
Share-based compensation expense						$ 115.7	154.1	296.7
Selling, general and administrative
Share-based Compensation Arrangement by Share-based Payment Award
Share-based compensation expense						187.8	198.6	371.7
Human Immunology Biosciences
Share-based Compensation Arrangement by Share-based Payment Award
Share-based compensation expense	$ 56.4					0.0	56.4	0.0
Human Immunology Biosciences \| Research and development
Share-based Compensation Arrangement by Share-based Payment Award
Share-based compensation expense	42.5
Human Immunology Biosciences \| Selling, general and administrative
Share-based Compensation Arrangement by Share-based Payment Award
Share-based compensation expense	$ 13.9
Reata Pharmaceuticals, Inc
Share-based Compensation Arrangement by Share-based Payment Award
Operating expenses		$ 393.4
Selling, general and administrative		196.4
Research and development expense		$ 197.0
Stock Options
Share-based Compensation Arrangement by Share-based Payment Award
Share based payment arrangement, term									10 years
Market Stock Units (MSUs)
Share-based Compensation Arrangement by Share-based Payment Award
Share-based compensation expense						$ 0.0	0.6	4.9
Vesting period									3 years
Number of equal annual increments \| increment						3
Percentage of earnings of the target number of units granted based on actual stock performance						0.00%
Percentage of earnings of the target number of units granted based on actual stock performance						200.00%
Total fair value of vested awards							6.3	20.7
Performance Units (PUs)
Share-based Compensation Arrangement by Share-based Payment Award
Total fair value of vested awards							13.2	28.6
PSUs Settled in Stock
Share-based Compensation Arrangement by Share-based Payment Award
Share-based compensation expense						$ 42.3	48.4	35.5
Vesting period				3 years
Percentage of earnings of the target number of units granted based on actual stock performance						0.00%
Percentage of earnings of the target number of units granted based on actual stock performance						200.00%
Granted (in dollars per share) \| $ / shares						$ 161.28
PSUs Settled in Cash
Share-based Compensation Arrangement by Share-based Payment Award
Share-based compensation expense						$ 0.0	$ (2.5)	6.8
Vesting period					3 years		3 years
Number of days for calculation of average closing stock price						30 days
Total fair value of vested awards							$ 9.5	$ 11.7
Granted (in dollars per share) \| $ / shares						$ 196.13	$ 280.60	$ 383.61
Time-Vested Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award
Share-based compensation expense						$ 249.3	$ 236.4	$ 220.0
Vesting period						3 years
Total fair value of vested awards						$ 141.6	$ 193.6	$ 232.1
Granted (in dollars per share) \| $ / shares						$ 141.71	$ 235.82	$ 282.92
2017 Omnibus Equity Plan \| Chief Executive Officer
Share-based Compensation Arrangement by Share-based Payment Award
Granted (in shares) \| shares									81,000
Stock options granted, weighted average price (in dollars per share) \| $ / shares									$ 139.10
Stock options granted, grant date fair value									$ 11.2
Vesting period									3 years
Omnibus Equity Plan 2024
Share-based Compensation Arrangement by Share-based Payment Award
Ratio of total number of shares reserved under the plan			1.5
Omnibus Plan number of shares authorized (in shares) \| shares			3,700,000
2024 Omnibus Equity Plan And 2024 ESPP
Share-based Compensation Arrangement by Share-based Payment Award
Number of share-based compensation plans pursuant to which awards are currently being made \| plan						2
Number Of Share Based Compensation Plans
Share-based Compensation Arrangement by Share-based Payment Award
Number of share-based compensation plans pursuant to which awards are currently being made \| plan						3