Investments in Equity Securities (Summary of Investments) (Details) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Investments [Line Items]
Investments	$ 23,861.0	$ 23,581.0
ABI [Member]
Investments [Line Items]
Investments in equity securities	18,453.0	18,071.0
JUUL [Member]
Investments [Line Items]
Equity securities without readily determinable fair value, amount	4,205.0	4,205.0
Cronos [Member]
Investments [Line Items]
Investments in equity securities	1,203.0	1,305.0
Equity Contract, Warrant [Member] \| Cronos [Member]
Investments [Line Items]
Derivative asset, fair value, gross asset	132.0	234.0
Equity Contract, Preemptive Rights [Member] \| Cronos [Member]
Investments [Line Items]
Derivative asset, fair value, gross asset	34.0	69.0
Common Stock [Member] \| Cronos [Member]
Investments [Line Items]
Investments in equity securities	$ 1,037.0	$ 1,002.0

[Line Items] for Investments [Table]

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