Investments in Equity Securities (Earnings in Equity Securities) (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Schedule of Equity Method Investments [Line Items]
Earnings from equity investments	$ 9	$ 447	$ 166	$ 533
ABI [Member]
Schedule of Equity Method Investments [Line Items]
Earnings from equity investments	(22)	302	112	388
Cronos Group Inc. [Member]
Schedule of Equity Method Investments [Line Items]
Earnings from equity investments	$ 31	$ 145	$ 54	$ 145

Amount of income (loss) for proportionate share of equity method investee's income (loss).

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