v3.20.4
Consolidated Balance Sheets (Parenthetical) - USD ($)
$ in Millions
Dec. 31, 2020
Dec. 31, 2019
Statement of Financial Position [Abstract]    
Allowance for doubtful accounts $ 508 $ 493
Current portion of long-term debt $ 2,002 $ 1,462
Preferred stock, shares authorized 27,000,000 27,000,000
Preferred stock, shares issued 0 431
Common stock, par value (in dollars per share) $ 0.05 $ 0.05
Common stock, shares authorized 12,000,000,000 12,000,000,000
Common stock, shares, issued 9,407,000,000 9,369,000,000
Treasury stock (in shares) 3,840,000,000 3,835,000,000