Contingencies (Judgments Paid and Provisions for Tobacco and Health Litigation) (Details) - USD ($) $ in Millions	3 Months Ended			9 Months Ended		12 Months Ended	168 Months Ended
	Sep. 30, 2018	Dec. 31, 2017	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2015	Sep. 30, 2018
Loss Contingency Accrual [Roll Forward]
Accrued liability for tobacco and health litigation items at beginning of period	$ 107	$ 47	$ 47	$ 106	$ 47
Payments	(21)		0	(118)	(18)
Accrued liability for tobacco and health litigation items at end of period	107	$ 106	47	107	47		$ 107
Interest Expense Related To Litigation [Member]
Loss Contingency Accrual [Roll Forward]
Pre-tax charges	1		0	15	2
Tobacco and Health Judgment [Member]
Loss Contingencies [Line Items]
Judgments paid (approximately)							578
Litigation settlement interest expense (income)							195
Tobacco and Health Judgment [Member] | Litigation Cases Results [Member]
Loss Contingency Accrual [Roll Forward]
Pre-tax charges	20		$ 0	104	$ 16
Engle Progeny Cases [Member]
Loss Contingencies [Line Items]
Judgments paid (approximately)							186
Litigation settlement interest expense (income)							33
PM USA [Member] | Engle Progeny Cases, Federal [Member]
Loss Contingencies [Line Items]
Payments made							43
Loss Contingency Accrual [Roll Forward]
Payments						$ (43)
Assets [Member] | Pending Litigation [Member] | PM USA [Member]
Loss Contingency Accrual [Roll Forward]
Security posted for appeal of judgments	$ 99			$ 99			$ 99