Other Comprehensive Earnings/Losses (Changes in Each Component of Accumulated Other Comprehensive Losses) (Details) - USD ($)
$ in Millions
 3 Months Ended 9 Months Ended 12 Months Ended
Sep. 30, 2016
Sep. 30, 2015
Sep. 30, 2016
Sep. 30, 2015
Dec. 31, 2015
Accumulated Other Comprehensive Income [Roll Forward]          
Beginning balance     $ 2,880    
Other comprehensive earnings (losses) before reclassifications $ 48 $ (496) (159) $ (931)  
Other comprehensive earnings (losses) before reclassifications, deferred income taxes (17) 174 66 325  
Other comprehensive earnings (losses) before reclassifications, net of deferred income taxes 31 (322) (93) (606)  
Amounts reclassified to net earnings 47 69 151 212  
Amounts reclassified to net earnings, deferred income taxes (16) (26) (56) (81)  
Amounts reclassified to net earnings, net of deferred income taxes 31 43 95 131  
Other comprehensive earnings (losses), net of deferred income taxes 62 (279) 2 (475) $ (598)
Ending balance 2,944   2,944   2,880
SABMiller [Member]          
Accumulated Other Comprehensive Income [Roll Forward]          
Other comprehensive earnings (losses) before reclassifications 48 (493) 158 (927)  
Other comprehensive earnings (losses) before reclassifications, deferred income taxes (17) 173 (56) 324  
Other comprehensive earnings (losses) before reclassifications, net of deferred income taxes 31 (320) 102 (603)  
Amounts reclassified to net earnings 5 5 24 14  
Amounts reclassified to net earnings, deferred income taxes (2) (2) (9) (4)  
Amounts reclassified to net earnings, net of deferred income taxes 3 3 15 10  
Other comprehensive earnings (losses), net of deferred income taxes 34 (317) 117 (593)  
Currency Translation Adjustments [Member]          
Accumulated Other Comprehensive Income [Roll Forward]          
Beginning balance (4) (3) (5) (2) (2)
Other comprehensive earnings (losses) before reclassifications 0 (3) 1 (4)  
Other comprehensive earnings (losses) before reclassifications, deferred income taxes 0 1 0 1  
Other comprehensive earnings (losses) before reclassifications, net of deferred income taxes 0 (2) 1 (3)  
Amounts reclassified to net earnings 0 0 0 0  
Amounts reclassified to net earnings, deferred income taxes 0 0 0 0  
Amounts reclassified to net earnings, net of deferred income taxes 0 0 0 0  
Other comprehensive earnings (losses), net of deferred income taxes 0 (2) 1 (3)  
Ending balance (4) (5) (4) (5) (5)
Benefit Plans [Member]          
Accumulated Other Comprehensive Income [Roll Forward]          
Beginning balance (2,154) (1,959) (2,010) (2,040) (2,040)
Other comprehensive earnings (losses) before reclassifications 0 0 (318) 0  
Other comprehensive earnings (losses) before reclassifications, deferred income taxes 0 0 122 0  
Other comprehensive earnings (losses) before reclassifications, net of deferred income taxes 0 0 (196) 0  
Amounts reclassified to net earnings 42 64 127 198  
Amounts reclassified to net earnings, deferred income taxes (14) (24) (47) (77)  
Amounts reclassified to net earnings, net of deferred income taxes 28 40 80 121  
Other comprehensive earnings (losses), net of deferred income taxes 28 40 (116) 121  
Ending balance (2,126) (1,919) (2,126) (1,919) (2,010)
AOCI Attributable to Parent [Member]          
Accumulated Other Comprehensive Income [Roll Forward]          
Beginning balance (3,340) (2,878) (3,280) (2,682) (2,682)
Other comprehensive earnings (losses), net of deferred income taxes     2   (598)
Ending balance (3,278) (3,157) (3,278) (3,157) (3,280)
AOCI Attributable to Parent [Member] | SABMiller [Member]          
Accumulated Other Comprehensive Income [Roll Forward]          
Beginning balance (1,182) (916) (1,265) (640) (640)
Ending balance $ (1,148) $ (1,233) $ (1,148) $ (1,233) $ (1,265)