Goodwill and Other Intangible Assets, net: (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended			12 Months Ended
	Jun. 30, 2025	Jun. 30, 2024	Mar. 31, 2024	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023	May 01, 2024
Finite-Lived Intangible Assets [Line Items]
Pre-tax impairment charge		$ 0	$ 27	$ 0	$ 27
Impairment, Intangible Asset, Indefinite-Lived (Excluding Goodwill), Statement of Income or Comprehensive Income [Extensible Enumeration]					Marketing, administration and research costs (Notes 3, 4, 11 & 18)
Finite-lived intangible asset				9,235	$ 8,943	$ 6,884
Estimated amortization expense, year one, assuming no additional transactions occur that require the amortization of intangible assets				987
Estimated amortization expense, year two, assuming no additional transactions occur that require the amortization of intangible assets				987
Estimated amortization expense, year three, assuming no additional transactions occur that require the amortization of intangible assets				987
Estimated amortization expense, year four, assuming no additional transactions occur that require the amortization of intangible assets				987
Estimated amortization expense, year five, assuming no additional transactions occur that require the amortization of intangible assets				987
Impairment of goodwill	$ 41	$ 0		41	0	665
Total assets				69,185	61,784
Cash and cash equivalents				4,872	4,216
In Process Research and Development
Finite-Lived Intangible Assets [Line Items]
Impairment of intangible assets						15
Wellness and Healthcare Segment
Finite-Lived Intangible Assets [Line Items]
Impairment of goodwill						$ 665
Reacquired commercialization rights for IQOS in the U.S.
Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible asset				$ 2,777	$ 2,777		$ 2,800
Megapolis
Finite-Lived Intangible Assets [Line Items]
Ownership interest				23.00%
Russia
Finite-Lived Intangible Assets [Line Items]
Total assets				$ 4,800
Cash and cash equivalents				$ 2,300