v3.19.3.a.u2
Incentive Program (Narrative) (Details) - USD ($)
shares in Thousands, $ in Millions
12 Months Ended
Dec. 31, 2019
Dec. 31, 2018
Dec. 31, 2017
Minimum ownership of affiliates needed for awards 50.00%    
Options and stock appreciation rights grant, minimum percentage of market value, date of grant 100.00%    
Share-based compensation arrangement by share-based payment award expiration period 10 years    
Number of shares issuable under 2003 incentive program, maximum 220,000    
Remaining shares available for award under 2003 incentive program 76,000    
Restricted Stock [Member]      
Long-term incentive awards 8,936 8,771 8,916
Percent of the shares in each award vesting after three years 50.00%    
Percent of shares in each award vesting after five years 50.00%    
Percent of the shares in each award vesting after seven years 50.00%    
Percent of shares in each award vesting in later of ten years or retirement 50.00%    
Unrecognized compensation cost $ 1,754    
Unrecognized compensation cost, weighted-average period of recognition, years 4 years 4 months 24 days    
Compensation cost charged against income $ 741 $ 774 $ 856
Income tax benefit recognized in income 51 42 78
Fair value of shares/awards vested 647 722 826
Cash payments, vested restricted stock units $ 56 $ 61 $ 64
Restricted Stock [Member] | Minimum [Member]      
Vesting Period 3 years    
Restricted Stock [Member] | Minimum [Member] | Executive Officer [Member]      
Vesting Period 5 years    
Restricted Stock [Member] | Maximum [Member]      
Vesting Period 7 years    
Restricted Stock [Member] | Maximum [Member] | Executive Officer [Member]      
Vesting Period 10 years