Investments in Equity Securities (Summary of Investments) (Details) - USD ($) $ in Millions	Sep. 30, 2019	Dec. 31, 2018
Investment [Line Items]
Investments	$ 27,346	$ 30,496
ABI [Member]
Investment [Line Items]
Investments in equity securities	17,950	17,696
JUUL [Member]
Investment [Line Items]
Equity securities, Fv-Ni	8,305	12,800
Cronos [Member]
Investment [Line Items]
Investments in equity securities	1,091	$ 0
Equity Contract, Warrant [Member] \| Cronos [Member]
Investment [Line Items]
Derivative asset, fair value, gross asset	315
Equity Contract, Preemptive Rights [Member] \| Cronos [Member]
Investment [Line Items]
Derivative asset, fair value, gross asset	103
Common Stock [Member] \| Cronos [Member]
Investment [Line Items]
Investments in equity securities	$ 673

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Fair value, before effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets elected not to be offset. Excludes assets not subject to a master netting arrangement.

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Sum of the carrying amounts as of the balance sheet date of all investments.

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