Share-Based Payments - Share-Based Compensation Expense Included In Statements Of Income (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2026	Sep. 30, 2025	Sep. 30, 2026	Sep. 30, 2025
Share-based Compensation Expense included in consolidated statements of income
Subtotal	$ 84.3	$ 78.4	$ 252.4	$ 240.6
Capitalized share-based compensation costs	(3.0)	(3.1)	(9.8)	(9.4)
Share-based compensation expense included in total cost and expense	81.3	75.3	242.6	231.2
Income tax effect	(16.0)	(14.4)	(47.7)	(45.3)
Income Statement Location [Axis]: us-gaap:NetIncomeLoss
Share-based Compensation Expense included in consolidated statements of income
Share-based compensation expense	65.3	60.9	194.9	185.9
Income Statement Location [Axis]: us-gaap:ResearchAndDevelopmentExpenseExcludingAcquiredInProcessCost
Share-based Compensation Expense included in consolidated statements of income
Share-based compensation expense	33.3	28.8	100.4	91.0
Income Statement Location [Axis]: us-gaap:SellingGeneralAndAdministrativeExpense
Share-based Compensation Expense included in consolidated statements of income
Share-based compensation expense	$ 51.0	$ 49.6	$ 152.0	$ 149.6

Share based compensation expense included in costs and expenses.

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section S45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479983/718-10-S45-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
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-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 14.F)
-Publisher FASB
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
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-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (h)(1)(i)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

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

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (h)(1)(i)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
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-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (h)(1)(ii)
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-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

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- Definition

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

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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