Contingencies (NPM Adjustment Disputes - Settlement with 20 States and Territories and Settlement with New York) (Details) $ in Millions	1 Months Ended						3 Months Ended		9 Months Ended	12 Months Ended		25 Months Ended
	Apr. 30, 2020 USD ($)	Apr. 30, 2019 USD ($)	Apr. 30, 2018 USD ($)	Oct. 31, 2017 USD ($) state	Sep. 30, 2013 USD ($) state	Nov. 30, 1998 state	Sep. 30, 2020 USD ($) state	Mar. 31, 2019 USD ($)	Sep. 30, 2020 USD ($) state claim	Dec. 31, 2018 USD ($) settlement_development	Dec. 31, 2017 USD ($) settlement_development	Apr. 30, 2020 USD ($)
Health Care Cost Recovery Actions [Member]
Loss Contingencies [Line Items]
Number of states with settled litigation | state						46
PM USA [Member] | Health Care Cost Recovery Actions [Member]
Loss Contingencies [Line Items]
Loss contingency, reduction to cost of sales								$ 52		$ 209	$ 39
Loss contingency, credits to offset payments							$ 361
Loss contingency, settlement agreement, payment period							9 years
PM USA [Member] | Health Care Cost Recovery Actions [Member] | Settled Litigation [Member]
Loss Contingencies [Line Items]
Loss contingency, number of states with settled litigation including New York, subsequent expansion | state									36
Settlement agreements, number | claim									2
Number of states with settled litigation | state									37
PM USA [Member] | Health Care Cost Recovery Actions, 2003-2015 NPM Adjustments [Member] | Settled Litigation [Member]
Loss Contingencies [Line Items]
Loss contingency, number of states with settled litigation including New York, subsequent expansion | state				26
​Proceeds from legal settlements				$ 740
Loss contingency, number of settlement developments | settlement_development										2	2
PM USA [Member] | Health Care Cost Recovery Actions, 2004-2017 [Member] | Settled Litigation [Member]
Loss Contingencies [Line Items]
Loss contingency, number of additional states added | state				10
Payments received from litigation settlement	$ 47	$ 121	$ 68									$ 248
Loss contingency, number of additional states extended with settled litigation | state							35
PM USA [Member] | Health Care Cost Recovery Actions, 2003 NPM Adjustment [Member] | Settled Litigation [Member]
Loss Contingencies [Line Items]
Number of states with settled litigation | state					2
PM USA [Member] | Health Care Cost Recovery Actions, 2003 NPM Adjustment [Member] | Pending Litigation [Member]
Loss Contingencies [Line Items]
Loss contingency, number of states | state					15
Number of states without defense | state					6
Loss contingency, number of disputes outstanding | state					2
PM USA [Member] | Health Care Cost Recovery Actions, 2003 NPM Adjustment [Member] | Pending Litigation [Member] | Cost of Sales [Member]
Loss Contingencies [Line Items]
Loss contingency, reduction to cost of sales					$ 74
PM USA [Member] | Health Care Cost Recovery Actions, 2004 NPM Adjustment [Member]
Loss Contingencies [Line Items]
Estimate of possible gain									$ 388
PM USA [Member] | Health Care Cost Recovery Actions, 2005 NPM Adjustment [Member]
Loss Contingencies [Line Items]
Estimate of possible gain									181
PM USA [Member] | Health Care Cost Recovery Actions, 2006 NPM Adjustment [Member]
Loss Contingencies [Line Items]
Estimate of possible gain									154
PM USA [Member] | Health Care Cost Recovery Actions, 2007 NPM Adjustment [Member]
Loss Contingencies [Line Items]
Estimate of possible gain									185
PM USA [Member] | Health Care Cost Recovery Actions, 2008 NPM Adjustment [Member]
Loss Contingencies [Line Items]
Estimate of possible gain									250
PM USA [Member] | Health Care Cost Recovery Actions, 2009 NPM Adjustment [Member]
Loss Contingencies [Line Items]
Estimate of possible gain									211
PM USA [Member] | Health Care Cost Recovery Actions, 2010 NPM Adjustment [Member]
Loss Contingencies [Line Items]
Estimate of possible gain									218
PM USA [Member] | Health Care Cost Recovery Actions, 2011 NPM Adjustment [Member]
Loss Contingencies [Line Items]
Estimate of possible gain									166
PM USA [Member] | Health Care Cost Recovery Actions, 2012 NPM Adjustment [Member]
Loss Contingencies [Line Items]
Estimate of possible gain									214
PM USA [Member] | Health Care Cost Recovery Actions, 2013 NPM Adjustment [Member]
Loss Contingencies [Line Items]
Estimate of possible gain									224
PM USA [Member] | Health Care Cost Recovery Actions, 2014 NPM Adjustment [Member]
Loss Contingencies [Line Items]
Estimate of possible gain									258
PM USA [Member] | Health Care Cost Recovery Actions, 2015 NPM Adjustments [Member]
Loss Contingencies [Line Items]
Estimate of possible gain									313
PM USA [Member] | Health Care Cost Recovery Actions, 2016 NPM Adjustments [Member]
Loss Contingencies [Line Items]
Estimate of possible gain									305
PM USA [Member] | Health Care Cost Recovery Actions, 2017 NPM Adjustments [Member]
Loss Contingencies [Line Items]
Estimate of possible gain									297
PM USA [Member] | Health Care Cost Recovery Actions, 2018 NPM Adjustments [Member]
Loss Contingencies [Line Items]
Estimate of possible gain									340
PM USA [Member] | Health Care Cost Recovery Actions, 2019 NPM Adjustments [Member]
Loss Contingencies [Line Items]
Estimate of possible gain									441
PM USA [Member] | Health Care Cost Recovery Actions, 2004 And Subsequent NPM Adjustment [Member]
Loss Contingencies [Line Items]
Loss contingency, credits to offset payments							$ 43
New York [Member] | PM USA [Member] | Health Care Cost Recovery Actions, Transition Years 2004-2018 [Member] | Settled Litigation [Member]
Loss Contingencies [Line Items]
​Proceeds from legal settlements									$ 317
Maryland, Missouri, New Mexico and Pennsylvania [Member] | PM USA [Member] | Health Care Cost Recovery Actions, 2003 NPM Adjustment [Member] | Pending Litigation [Member]
Loss Contingencies [Line Items]
Loss contingency, number of states remaining | state					4