Quarterly report pursuant to Section 13 or 15(d)

Common Stock And Cash Incentive Bonuses (Details)

v3.20.2
Common Stock And Cash Incentive Bonuses (Details)
$ in Millions
 3 Months Ended 9 Months Ended
Jan. 21, 2020
USD ($)
item
shares
Sep. 30, 2019
shares
Sep. 30, 2020
USD ($)
shares
Sep. 30, 2019
shares
Equity, Class of Treasury Stock [Line Items]        
Spin-off cash incentive bonus | $     $ 19.5  
Restricted Stock [Member]        
Equity, Class of Treasury Stock [Line Items]        
Aggregate fair value on grant date | $     16.7  
Compensation cost | $     $ 19.8  
Restricted Stock [Member] | Class A Common Stock [Member]        
Equity, Class of Treasury Stock [Line Items]        
Unvested restricted shares     488,503  
Restricted Stock [Member] | Class B Common Stock [Member]        
Equity, Class of Treasury Stock [Line Items]        
Unvested restricted shares     528,484  
Restricted Stock [Member] | Executive Officers [Member] | Class B Common Stock [Member]        
Equity, Class of Treasury Stock [Line Items]        
Number of shares granted 488,503      
Aggregate fair value on grant date | $ $ 10.2      
Number of shares vested 122,125      
Number of annual installments vested | item 4      
Restricted Stock [Member]        
Equity, Class of Treasury Stock [Line Items]        
Unvested restricted shares     0  
Anti-dilutive shares   3,039,265   3,039,265