Contingencies (NPM Adjustment Disputes - Settlement with 20 States and Territories and Settlement with New York) (Details) $ in Millions	1 Months Ended							3 Months Ended					12 Months Ended
	Apr. 29, 2021 USD ($)	Apr. 30, 2020 USD ($)	Apr. 30, 2019 USD ($)	Apr. 30, 2018 USD ($)	Oct. 31, 2017 USD ($) state	Sep. 30, 2013 USD ($) state	Nov. 30, 1998 state	Mar. 31, 2021 USD ($) state claim	Dec. 31, 2020 USD ($)	Sep. 30, 2020 USD ($) state	Mar. 31, 2020 USD ($)	Mar. 31, 2019 USD ($)	Dec. 31, 2018 USD ($) settlement_development state	Dec. 31, 2017 USD ($)
Health Care Cost Recovery Actions [Member]
Loss Contingencies [Line Items]
Number of states with settled litigation | state							46
Litigation settlement								$ 900.0			$ 1,100.0
PM USA [Member] | Health Care Cost Recovery Actions [Member]
Loss Contingencies [Line Items]
Loss contingency, reduction to cost of sales												$ 52.0	$ 209.0	$ 39.0
Loss contingency, credits to offset payments										$ 361.0
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								3
Number of states with settled litigation | state								38
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					$ 740.0
Loss contingency, number of settlement developments | settlement_development													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		$ 47.0	$ 121.0	$ 68.0				$ 248.0
Loss contingency, number of additional states extended with settled litigation | state										35
PM USA [Member] | Health Care Cost Recovery Actions, 2004-2017 [Member] | Settled Litigation [Member] | Subsequent Event [Member]
Loss Contingencies [Line Items]
Payments received from litigation settlement	$ 8.0
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						$ 74.0
PM USA [Member] | Health Care Cost Recovery Actions, 2004 NPM Adjustment [Member]
Loss Contingencies [Line Items]
Loss contingency, damages sought, value		$ 13.8
Litigation settlement									$ 4.0
Estimate of possible gain								388.0
PM USA [Member] | Health Care Cost Recovery Actions, 2005 NPM Adjustment [Member]
Loss Contingencies [Line Items]
Estimate of possible gain								181.0
PM USA [Member] | Health Care Cost Recovery Actions, 2006 NPM Adjustment [Member]
Loss Contingencies [Line Items]
Estimate of possible gain								154.0
PM USA [Member] | Health Care Cost Recovery Actions, 2007 NPM Adjustment [Member]
Loss Contingencies [Line Items]
Estimate of possible gain								185.0
PM USA [Member] | Health Care Cost Recovery Actions, 2008 NPM Adjustment [Member]
Loss Contingencies [Line Items]
Estimate of possible gain								250.0
PM USA [Member] | Health Care Cost Recovery Actions, 2009 NPM Adjustment [Member]
Loss Contingencies [Line Items]
Estimate of possible gain								211.0
PM USA [Member] | Health Care Cost Recovery Actions, 2010 NPM Adjustment [Member]
Loss Contingencies [Line Items]
Estimate of possible gain								218.0
PM USA [Member] | Health Care Cost Recovery Actions, 2011 NPM Adjustment [Member]
Loss Contingencies [Line Items]
Estimate of possible gain								166.0
PM USA [Member] | Health Care Cost Recovery Actions, 2012 NPM Adjustment [Member]
Loss Contingencies [Line Items]
Estimate of possible gain								214.0
PM USA [Member] | Health Care Cost Recovery Actions, 2013 NPM Adjustment [Member]
Loss Contingencies [Line Items]
Estimate of possible gain								224.0
PM USA [Member] | Health Care Cost Recovery Actions, 2014 NPM Adjustment [Member]
Loss Contingencies [Line Items]
Estimate of possible gain								258.0
PM USA [Member] | Health Care Cost Recovery Actions, 2015 NPM Adjustments [Member]
Loss Contingencies [Line Items]
Estimate of possible gain								313.0
PM USA [Member] | Health Care Cost Recovery Actions, 2016 NPM Adjustments [Member]
Loss Contingencies [Line Items]
Estimate of possible gain								292.0
PM USA [Member] | Health Care Cost Recovery Actions, 2017 NPM Adjustments [Member]
Loss Contingencies [Line Items]
Estimate of possible gain								302.0
PM USA [Member] | Health Care Cost Recovery Actions, 2018 NPM Adjustments [Member]
Loss Contingencies [Line Items]
Estimate of possible gain								325.0
PM USA [Member] | Health Care Cost Recovery Actions, 2019 NPM Adjustments [Member]
Loss Contingencies [Line Items]
Estimate of possible gain								444.0
PM USA [Member] | Health Care Cost Recovery Actions, 2020 NPM Adjustments [Member]
Loss Contingencies [Line Items]
Estimate of possible gain								572.0
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								$ 373.0
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