Quarterly Financial Data (Unaudited) (Schedule of Pre-tax Charges or (Gains) Included in Net Earnings Attributable to Altria Group, Inc.) (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Investments [Line Items]
Impairment of JUUL equity securities	$ 0	$ 2,600	$ 0	$ 0	$ 4,100	$ 4,500	$ 0	$ 0	$ 2,600	$ 8,600	$ 0
Tobacco and health litigation items, including accrued interest	7	34	18	24	29	3	28	17
Asset impairment, exit, implementation and acquisition-related costs	16	12	8	395	116	11	45	159
PMCC residual value adjustments	91	0	34	0
Cost of sales									7,818	7,085	7,373
Pre-tax charges (gains) included in net earnings	(5)	3,302	142	564	3,686	5,040	63	764
COVID-19 [Member]
Investments [Line Items]
Cost of sales	0	0	50	0					50
ABI [Member]
Investments [Line Items]
Investment special items	74	513	120	56	(394)	(23)	(129)	163
Cronos [Member]
Investments [Line Items]
Investment special items	(93)	143	(88)	89	(165)	549	$ 119	$ 425
JUUL [Member]
Investments [Line Items]
Impairment of JUUL equity securities					$ 4,100	$ 4,500			2,600	8,600
JUUL changes in fair value	$ (100)	$ 0	$ 0	$ 0					$ (100)	$ 0	$ 0