Investments in Equity Securities (Summary of Investments) (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Investments [Line Items]
Investments	$ 23,581	$ 30,496
ABI [Member]
Investments [Line Items]
Equity method investments	18,071	17,696
JUUL [Member]
Investments [Line Items]
Equity securities without readily determinable fair value, amount	4,205	12,800
Cronos [Member]
Investments [Line Items]
Equity method investments	1,305	0
Common Stock [Member] \| Cronos [Member]
Investments [Line Items]
Equity method investments	1,002
Net Investment Hedging [Member]
Investments [Line Items]
Fair value of assets	349	41
Not Designated as Hedging Instrument [Member] \| Net Investment Hedging [Member] \| Investments In Equity Securities [Member] \| Equity Contract, Warrant [Member]
Investments [Line Items]
Fair value of assets	234	0
Not Designated as Hedging Instrument [Member] \| Net Investment Hedging [Member] \| Investments In Equity Securities [Member] \| Equity Contract, Preemptive Rights [Member]
Investments [Line Items]
Fair value of assets	$ 69	$ 0

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