v3.10.0.1
Business Acquisitions - Additional Information (Details) - USD ($)
$ in Millions
 1 Months Ended 10 Months Ended 12 Months Ended
Jul. 31, 2017
May 31, 2017
Aug. 31, 2016
Mar. 31, 2016
Dec. 31, 2017
Dec. 31, 2016
Business Acquisition [Line Items]            
Goodwill deductible for tax purposes         $ 30.3  
RSUs and RSAs to certain continuing employees in exchange for future service         171.1  
Additional purchase consideration payment in stock and cash           $ 255.2
Acquired Developed Technology            
Business Acquisition [Line Items]            
Intangible assets deductible for tax purposes         40.1  
Customer Relationships            
Business Acquisition [Line Items]            
Intangible assets deductible for tax purposes         1.6  
Placed, Inc.            
Business Acquisition [Line Items]            
Total consideration including compensation paid in cash $ 185.9          
Total purchase consideration 139.6          
Business acquisition, purchase price cash consideration 135.2          
Business acquisition, fair value of assumed options 3.9          
Purchase consideration, liabilities assumed 0.5          
Business acquisition, compensation transferred for future employment service $ 46.3          
Zenly SAS            
Business Acquisition [Line Items]            
Total consideration including compensation paid in cash   $ 213.3        
Total purchase consideration   196.1        
Business acquisition, purchase price cash consideration   186.8        
Purchase consideration, liabilities assumed   9.3        
Business acquisition, compensation transferred for future employment service   $ 17.2        
Other Acquisitions            
Business Acquisition [Line Items]            
Total purchase consideration         101.9  
Business acquisition, purchase price cash consideration         95.3  
Other Acquisitions | Other Liabilities            
Business Acquisition [Line Items]            
Purchase consideration, liabilities assumed         $ 6.6  
Bitstrips Inc.            
Business Acquisition [Line Items]            
Total purchase consideration       $ 64.2    
Business acquisition, purchase price cash consideration       46.6    
Bitstrips Inc. | Non-Voting Class A Common Stock            
Business Acquisition [Line Items]            
Business acquisition, fair value of assumed options       11.6    
Bitstrips Inc. | Accrued Expenses and Other Current Liabilities            
Business Acquisition [Line Items]            
Purchase consideration, liabilities assumed       $ 6.0    
Mobile Search Company            
Business Acquisition [Line Items]            
Total purchase consideration     $ 114.5      
Business acquisition, purchase price cash consideration     21.0      
Mobile Search Company | Non-Voting Class A Common Stock            
Business Acquisition [Line Items]            
Business acquisition, fair value of assumed options     83.0      
Mobile Search Company | Other Liabilities            
Business Acquisition [Line Items]            
Purchase consideration, liabilities assumed     $ 10.5      
Computer Vision Software Company            
Business Acquisition [Line Items]            
Total purchase consideration           47.0
Goodwill deductible for tax purposes           30.7
Computer Vision Software Company | Acquired Developed Technology            
Business Acquisition [Line Items]            
Intangible assets deductible for tax purposes           9.8
Computer Vision Software Company | Other Liabilities            
Business Acquisition [Line Items]            
Purchase consideration, liabilities assumed           $ 4.6