v3.22.0.1
Share-Based Payments (Summary Of Activity Related To Stock Options) (Details) - USD ($)
$ / shares in Units, $ in Millions
12 Months Ended
Dec. 31, 2021
Dec. 31, 2020
Dec. 31, 2019
Dec. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]        
Number of Options, Outstanding at beginning of period 26,671 967,769 1,724,723  
Number of Options, Granted 0 0 0  
Number of Options, Exercised (26,671) (911,181) (756,954)  
Number of Options, Forfeited or Expired 0 (29,917) 0  
Number of Options, Outstanding at end of period 0 26,671 967,769 1,724,723
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Number 0 years      
Number of Options, Exercisable at end of period 0      
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Abstract]        
Weighted-Average Exercise Price, Outstanding at beginning of period $ 6.54 $ 6.80 $ 6.86  
Weighted-Average Exercise Price, Granted 0 0 0  
Weighted-Average Exercise Price, Exercised 6.54 6.80 6.93  
Weighted-Average Exercise Price, Forfeited or Expired 0 7.00 0  
Weighted-Average Exercise Price, Outstanding at end of period 0 $ 6.54 $ 6.80 $ 6.86
Weighted-Average Exercise Price, Exercisable at end of period $ 0      
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract]        
Aggregate Intrinsic Value, at end of period $ 0 $ 0 $ 10 $ 11
Aggregate intrinsic Value, Exercisable at end of period $ 0      
Weighted-Average Contractual Term (in years), Outstanding 0 years 4 months 28 days 9 months 29 days 1 year 8 months 26 days