XML 81 R67.htm IDEA: XBRL DOCUMENT v3.19.1
Commitments and Contingencies (Details)
$ in Millions
12 Months Ended
Dec. 31, 2018
USD ($)
Officer
Dec. 31, 2017
USD ($)
Dec. 31, 2016
USD ($)
Operating Leased Assets [Abstract]      
Rent expense $ 37.1 $ 34.8 $ 30.3
Renewal period of employment agreements 2 years    
Expiration date Dec. 31, 2019    
Future compensation - 2019 $ 31.6    
Future compensation - 2020 through 2022 $ 7.4    
Executive Officer [Member]      
Operating Leased Assets [Abstract]      
Number of officers with the company had employee agreement | Officer 4    
Minimum [Member]      
Operating Leased Assets [Abstract]      
Operating leases renewal period 1 year    
Maximum [Member]      
Operating Leased Assets [Abstract]      
Operating leases renewal period 5 years