Contingencies (Judgments Paid and Provisions for Tobacco and Health Litigation) (Details) $ in Millions	3 Months Ended		9 Months Ended		12 Months Ended	192 Months Ended
	Sep. 30, 2020 USD ($) case	Sep. 30, 2019 USD ($)	Sep. 30, 2020 USD ($) case	Sep. 30, 2019 USD ($)	Dec. 31, 2019 USD ($)	Sep. 30, 2020 USD ($) case
Loss Contingency Accrual [Roll Forward]
Accrued liability for tobacco and health litigation items at beginning of period	$ 22	$ 13	$ 14	$ 112	$ 112
Payments	(47)	(7)	(81)	(151)
Accrued liability for tobacco and health litigation items at end of period	9	9	9	9	$ 14	$ 9
Pre-Trial Resolution [Member]
Loss Contingency Accrual [Roll Forward]
Payments			(20)
Accrued liability for tobacco and health litigation items at end of period	2		2			2
Interest Expense Related to Litigation [Member]
Loss Contingency Accrual [Roll Forward]
Provision related to litigation recorded	0	0	3	5
Assets [Member] | Pending Litigation [Member] | PM USA [Member]
Loss Contingency Accrual [Roll Forward]
Security posted for appeal of judgments	$ 61		61			61
Tobacco and Health Judgment [Member]
Loss Contingencies [Line Items]
Judgments paid (approximately)						798
Litigation settlement interest expense (income)						$ 217
Tobacco and Health Judgment [Member] | Pre-Trial Resolution [Member]
Loss Contingency Accrual [Roll Forward]
Provision related to litigation recorded			$ 20
Loss contingency, number of pre-trial resolution cases | case	240		240			240
Tobacco and Health Judgment [Member] | Litigation Cases Results [Member]
Loss Contingency Accrual [Roll Forward]
Provision related to litigation recorded	$ 34	$ 3	$ 73	$ 43
Engle Progeny Cases [Member]
Loss Contingencies [Line Items]
Judgments paid (approximately)						$ 364
Litigation settlement interest expense (income)						$ 55