v3.19.3
Redeemable Convertible Preferred Stock, Common Stock, and Equity (Deficit) - Narrative (Details) - USD ($)
$ / shares in Units, $ in Millions
1 Months Ended 3 Months Ended 9 Months Ended
May 16, 2019
May 14, 2019
Jan. 31, 2019
Sep. 30, 2019
Sep. 30, 2018
Sep. 30, 2019
Sep. 30, 2018
Jun. 30, 2019
Apr. 30, 2019
Mar. 31, 2019
Dec. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                      
Preferred stock, shares authorized (in shares)       10,000,000   10,000,000          
Preferred stock, shares issued (in shares)       0   0          
Preferred stock, shares outstanding (in shares)       0   0          
Incremental stock-based compensation costs relating to modification of awards             $ 52        
Share-based compensation expense       $ 401 $ 64 $ 4,353 $ 147        
Restricted Stock Awards, Restricted Stock Units, and Stock Appreciation Rights                      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                      
Unamortized compensation costs       $ 2,400   $ 2,400          
Weighted-average recognition period           2 years 4 months 24 days          
2013 Plan                      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                      
Increase in stock reserved for issuance (in shares)     85,000,000                
Number of shares reserved for future issuance (in shares)     293,000,000                
2019 Plan                      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                      
Number of shares reserved for future issuance (in shares)                 130,000,000    
Equity incentive plan, term over which available awards may increase           10 years          
Equity incentive plan, percent of increase           5.00%          
ESPP 2019                      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                      
Number of shares reserved for future issuance (in shares)       25,000,000   25,000,000          
ESPP, percent of total shares outstanding, increase calculation                   1.00%  
ESPP, upper threshold on increase in authorized shares (in shares)               25,000,000      
IPO                      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                      
Conversion of shares (in shares)   905,000,000                  
Stock issued during period (in shares)   180,000,000                  
Stock price (in dollars per share) $ 45.00 $ 45.00                  
Proceeds from issuance of common stock   $ 8,000                  
Share-based compensation expense   $ 3,600                  
Shares withheld to meet tax withholding requirements (in shares)   29,000,000                  
Shares withheld to meet tax withholding requirement, value   $ 1,300                  
Private Placement                      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                      
Stock issued during period (in shares) 11,000,000                    
Proceeds from issuance of common stock $ 500                    
Series E Redeemable Convertible Preferred Stock                      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                      
Number of securities called by warrants (in shares)                     150,071
Series G Redeemable Convertible Preferred Stock                      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                      
Number of securities called by warrants (in shares)                     922,655
Common Stock | IPO                      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                      
Stock issued during period (in shares)   76,000,000