XML 61 R48.htm IDEA: XBRL DOCUMENT v3.20.4
Summary of Significant Accounting Policies - Property, Plant and Equipment (Details) - USD ($)
$ in Millions
12 Months Ended
Dec. 31, 2020
Dec. 31, 2019
Property, Plant and Equipment [Line Items]    
Property and equipment $ 809.7 $ 770.3
Less: accumulated depreciation and amortization (552.4) (511.7)
Property and equipment, net 257.3 258.6
Computer equipment    
Property, Plant and Equipment [Line Items]    
Property and equipment $ 464.1 434.8
Estimated useful life 3 years  
Software    
Property, Plant and Equipment [Line Items]    
Property and equipment $ 64.8 55.9
Software | Minimum    
Property, Plant and Equipment [Line Items]    
Estimated useful life 3 years  
Software | Maximum    
Property, Plant and Equipment [Line Items]    
Estimated useful life 5 years  
Land    
Property, Plant and Equipment [Line Items]    
Property and equipment $ 9.0 9.0
Buildings, including improvements    
Property, Plant and Equipment [Line Items]    
Property and equipment $ 146.6 145.5
Buildings, including improvements | Minimum    
Property, Plant and Equipment [Line Items]    
Estimated useful life 5 years  
Buildings, including improvements | Maximum    
Property, Plant and Equipment [Line Items]    
Estimated useful life 40 years  
Leasehold improvements    
Property, Plant and Equipment [Line Items]    
Property and equipment $ 98.2 99.4
Other    
Property, Plant and Equipment [Line Items]    
Property and equipment $ 27.0 $ 25.7
Other | Minimum    
Property, Plant and Equipment [Line Items]    
Estimated useful life 1 year  
Other | Maximum    
Property, Plant and Equipment [Line Items]    
Estimated useful life 20 years