Investments in Equity Securities (Summary of Investments) (Details) - USD ($) $ in Millions	Sep. 30, 2020	Dec. 31, 2019
Investments [Line Items]
Investments	$ 19,408	$ 23,581
ABI [Member]
Investments [Line Items]
Investments in equity securities	16,716	18,071
JUUL [Member]
Investments [Line Items]
Equity securities without readily determinable fair value, amount	1,605	4,205
Cronos [Member]
Investments [Line Items]
Investments in equity securities	1,087	1,305
Equity Contract, Warrant [Member] \| Cronos [Member]
Investments [Line Items]
Derivative asset, fair value, gross asset	86	234
Equity Contract, Preemptive Rights [Member] \| Cronos [Member]
Investments [Line Items]
Derivative asset, fair value, gross asset	15	69
Common Stock [Member] \| Cronos [Member]
Investments [Line Items]
Investments in equity securities	$ 986	$ 1,002

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