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Long-Term Debt (Details) - USD ($) $ in Millions	1 Months Ended
	Oct. 31, 2025	Sep. 30, 2025
Verona Pharma plc | Subsequent Event
Debt Instrument [Line Items]
Consideration transferred, asset acquisition	$ 10,500
Senior Notes
Debt Instrument [Line Items]
Face amount of debt		$ 6,000
Floating Rate Notes Due 2027 | Senior Notes
Debt Instrument [Line Items]
Face amount of debt		500
3.85% notes due 2027 | Senior Notes
Debt Instrument [Line Items]
Face amount of debt		$ 750
Stated interest rate		3.85%
4.15% notes due 2030 | Senior Notes
Debt Instrument [Line Items]
Face amount of debt		$ 750
Stated interest rate		4.15%
4.55% notes due 2032 | Senior Notes
Debt Instrument [Line Items]
Face amount of debt		$ 1,000
Stated interest rate		4.55%
4.95% notes due 2035 | Senior Notes
Debt Instrument [Line Items]
Face amount of debt		$ 1,750
Stated interest rate		4.95%
5.70% notes due 2055 | Senior Notes
Debt Instrument [Line Items]
Face amount of debt		$ 1,250
Stated interest rate		5.70%

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