v3.10.0.1
Summary of Significant Accounting Policies - Additional Information (Details)
 1 Months Ended 3 Months Ended 12 Months Ended
Oct. 26, 2016
Mar. 31, 2017
USD ($)
$ / shares
shares
Mar. 31, 2017
USD ($)
$ / shares
shares
Dec. 31, 2018
USD ($)
$ / shares
shares
Dec. 31, 2017
USD ($)
shares
Dec. 31, 2016
USD ($)
Summary Of Significant Accounting Policies [Line Items]            
Net proceeds from initial public offering       $ 0 $ 2,657,797,000 $ 0
Stock-based compensation expense       538,211,000 2,639,895,000 31,842,000
Tax withholding obligation       551,000 394,156,000 0
Advertising revenue-share cost       $ 120,300,000 $ 96,300,000 $ 57,800,000
Type of Cost, Good or Service [Extensible List]       us-gaap:AdvertisingMember us-gaap:AdvertisingMember us-gaap:AdvertisingMember
Advertising cost       $ 11,300,000 $ 10,900,000 $ 9,400,000
Percentage of tax benefits likelihood of being realized       greater than 50%    
Highly liquid investments with original maturities       90 days or less    
Lease exit charges       $ 33,033,000 $ 0 $ 0
Number of operating segment       1 1 1
Number of reporting unit       1 1 1
Goodwill impairment charges       $ 0 $ 0 $ 0
General and Administrative Expense            
Summary Of Significant Accounting Policies [Line Items]            
Stock-based compensation expense       109,226,000 1,222,920,000 $ 5,419,000
Lease exit charges       33,000,000    
Build-to-suit Leases            
Summary Of Significant Accounting Policies [Line Items]            
Assets capitalized       54,100,000 54,000,000  
Leases assets depreciation expense       $ 0 $ 0  
Computer Hardware and Software            
Summary Of Significant Accounting Policies [Line Items]            
Property and equipment estimated useful life       3 years    
Furniture and Equipment            
Summary Of Significant Accounting Policies [Line Items]            
Property and equipment estimated useful life       5 years    
Minimum | Buildings            
Summary Of Significant Accounting Policies [Line Items]            
Property and equipment estimated useful life       25 years    
Maximum            
Summary Of Significant Accounting Policies [Line Items]            
Business combination measurement period       1 year    
Maximum | Buildings            
Summary Of Significant Accounting Policies [Line Items]            
Property and equipment estimated useful life       45 years    
Pre-2017 RSUs            
Summary Of Significant Accounting Policies [Line Items]            
Initial public offering price per share | $ / shares       $ 17.00    
Shares withheld for payroll taxes | shares     12,100,000      
Common stock issued | shares       26,700,000    
Tax withholding obligation     $ 206,600,000      
Pre-2017 RSUs | First Year            
Summary Of Significant Accounting Policies [Line Items]            
Award vesting percentage       10.00%    
Pre-2017 RSUs | Second Year            
Summary Of Significant Accounting Policies [Line Items]            
Award vesting percentage       20.00%    
Pre-2017 RSUs | Third Year            
Summary Of Significant Accounting Policies [Line Items]            
Award vesting percentage       30.00%    
Pre-2017 RSUs | Fourth Year            
Summary Of Significant Accounting Policies [Line Items]            
Award vesting percentage       40.00%    
Restricted Stock Units            
Summary Of Significant Accounting Policies [Line Items]            
Share based compensation arrangement by share based payment award vesting | shares       22,400,000 34,400,000  
Post-2017 RSUs            
Summary Of Significant Accounting Policies [Line Items]            
Service condition satisfied, years       4 years    
Post-2017 RSUs | First Year            
Summary Of Significant Accounting Policies [Line Items]            
Award vesting percentage       10.00%    
Post-2017 RSUs | Second Year            
Summary Of Significant Accounting Policies [Line Items]            
Award vesting percentage       20.00%    
Post-2017 RSUs | Third Year            
Summary Of Significant Accounting Policies [Line Items]            
Award vesting percentage       30.00%    
Post-2017 RSUs | Fourth Year            
Summary Of Significant Accounting Policies [Line Items]            
Award vesting percentage       40.00%    
IPO | Pre-2017 RSUs            
Summary Of Significant Accounting Policies [Line Items]            
Stock-based compensation expense       $ 1,300,000,000    
Class A Common Stock            
Summary Of Significant Accounting Policies [Line Items]            
Stock split ratio 1.00          
Stock split description       One share of Class A common stock was distributed for each share of preferred stock and common stock outstanding (the “Stock Split”).    
Class A Common Stock | Restricted Stock Units            
Summary Of Significant Accounting Policies [Line Items]            
Share based compensation arrangement by share based payment award vesting | shares       50,701,000    
Class A Common Stock | IPO            
Summary Of Significant Accounting Policies [Line Items]            
Common stock, shares issued and sold | shares   160,300,000   160,300,000    
Initial public offering price per share | $ / shares   $ 17.00 $ 17.00      
Net proceeds from initial public offering   $ 2,600,000,000        
Underwriting discounts and commissions   68,100,000        
Other stock offering expenses   $ 14,700,000        
Class B Common Stock            
Summary Of Significant Accounting Policies [Line Items]            
Common stock issued | shares       93,845,185    
Class B Common Stock | Restricted Stock Units            
Summary Of Significant Accounting Policies [Line Items]            
Share based compensation arrangement by share based payment award vesting | shares       6,331,000    
Class B Common Stock | IPO | Convertible Preferred Stock Other Than Series FP Preferred Stock            
Summary Of Significant Accounting Policies [Line Items]            
Conversion of convertible preferred stock into common stock | shares   246,800,000        
Class C Common Stock            
Summary Of Significant Accounting Policies [Line Items]            
Common stock issued | shares       224,611,365    
Class C Common Stock | CEO            
Summary Of Significant Accounting Policies [Line Items]            
Common stock issued | shares         3,100,000  
Shares to be issued in future periods | shares         34,300,000  
Class C Common Stock | IPO | CEO            
Summary Of Significant Accounting Policies [Line Items]            
Common stock issued | shares       12,500,000    
Shares to be issued in future periods | shares       21,800,000    
Class C Common Stock | IPO | Restricted Stock Units | CEO            
Summary Of Significant Accounting Policies [Line Items]            
Initial public offering price per share | $ / shares       $ 17.00    
Stock-based compensation expense       $ 636,600,000    
Percentage of outstanding shares       3.00%    
Share based compensation arrangement by share based payment award vesting | shares       37,400,000    
Vested awards, distribution period       3 years    
Vested awards, distribution description       The CEO award vested immediately on the closing of the IPO, and such shares are being delivered to the CEO in quarterly installments over three years which began in November 2017.    
Class C Common Stock | IPO | Series FP Preferred Stock            
Summary Of Significant Accounting Policies [Line Items]            
Stock split ratio       1    
Conversion of convertible preferred stock into common stock | shares   215,900,000        
Class C Common Stock | IPO | Series FP Preferred Stock | Restricted Stock Units            
Summary Of Significant Accounting Policies [Line Items]            
Conversion of convertible preferred stock into common stock | shares       37,400,000    
Class C Common Stock | IPO | Series FP Preferred Stock | Restricted Stock Units | CEO            
Summary Of Significant Accounting Policies [Line Items]            
Conversion of convertible preferred stock into common stock | shares       37,400,000