CONDENSED CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) $ in Millions	Sep. 30, 2020	Dec. 31, 2019
Current assets:
Accounts receivable, allowances for doubtful accounts	$ 311	$ 206
Stockholders' equity:
Common stock, par value (in dollars per share)	$ 0.000006	$ 0.000006
Class A Common Stock
Stockholders' equity:
Common stock, shares authorized (in shares)	5,000,000,000	5,000,000,000
Common stock, shares issued (in shares)	2,406,000,000	2,407,000,000
Common stock, shares outstanding (in shares)	2,406,000,000	2,407,000,000
Class B Common Stock
Stockholders' equity:
Common stock, shares authorized (in shares)	4,141,000,000	4,141,000,000
Common stock, shares issued (in shares)	444,000,000	445,000,000
Common stock, shares outstanding (in shares)	444,000,000	445,000,000