Contingencies (Judgments Paid and Provisions for Tobacco and Health Litigation) (Details) - USD ($) $ in Millions	3 Months Ended			12 Months Ended	234 Months Ended
	Mar. 31, 2024	Dec. 31, 2023	Mar. 31, 2023	Dec. 31, 2021	Mar. 31, 2024
Loss Contingency Accrual [Roll Forward]
Accrued liability for tobacco and health litigation items at beginning of period	$ 346		$ 71
Loss contingency accrual, provision				$ 90
Payments	(6)		(11)
Accrued liability for tobacco and health litigation items at end of period	364	$ 346	171		$ 364
Related Interest Costs [Member]
Loss Contingency Accrual [Roll Forward]
Loss contingency accrual, provision	0		1
Assets [Member] | Pending Litigation [Member] | PM USA [Member]
Loss Contingencies [Line Items]
Security posted for appeal of judgments	38				38
Tobacco and Health Judgment [Member]
Loss Contingencies [Line Items]
Judgments paid					1,000
Litigation settlement interest expense (income)					241
Tobacco and Health Judgment [Member] | Tobacco and Health and Certain Other Litigation [Member]
Loss Contingency Accrual [Roll Forward]
Loss contingency accrual, provision	18		12
Engle Progeny Cases [Member]
Loss Contingencies [Line Items]
Judgments paid					440
Litigation settlement interest expense (income)					$ 60
Agreement To Resolve Shareholder Class Action | Tobacco and Health and Certain Other Litigation [Member]
Loss Contingency Accrual [Roll Forward]
Loss contingency accrual, provision	0		98
JUUL-related settlements [Member] | Tobacco and Health and Certain Other Litigation [Member]
Loss Contingency Accrual [Roll Forward]
Loss contingency accrual, provision	$ 6		$ 0
Health Care Cost Recovery Actions, 2005-2007 NPM Adjustment [Member] | Pending Litigation [Member] | PM USA [Member]
Loss Contingencies [Line Items]
Litigation settlement interest expense (income)		$ (21)