Investments in Equity Securities (Summary of Investments) (Details) - USD ($) $ in Millions	Jun. 30, 2019	Dec. 31, 2018
Investment [Line Items]
Investments in equity securities	$ 32,094	$ 30,496
Investments	32,094	30,496
ABI [Member]
Investment [Line Items]
Investments in equity securities	17,669	17,696
JUUL [Member]
Investment [Line Items]
Equity securities, Fv-Ni	12,805	12,800
Cronos Group Inc. [Member]
Investment [Line Items]
Investments in equity securities	1,620	$ 0
Equity Contract, Warrant [Member] \| Cronos Group Inc. [Member]
Investment [Line Items]
Derivative asset, fair value, gross asset	763
Equity Contract, Preemptive Rights [Member] \| Cronos Group Inc. [Member]
Investment [Line Items]
Derivative asset, fair value, gross asset	313
Common Stock [Member] \| Cronos Group Inc. [Member]
Investment [Line Items]
Investments in equity securities	$ 544

Line items represent reporting concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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