CONSOLIDATED BALANCE SHEET (Parentheticals) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Statement of Financial Position [Abstract]
Allowance for doubtful accounts	$ 97	$ 82
Common stock - par value (in usd per share)	$ 0.001	$ 0.001
Common stock - shares authorized	3,580,000,000	3,580,000,000
Common stock - shares outstanding	684,000,000	796,000,000
Treasury stock - shares	1,021,000,000	897,000,000