Quarterly report pursuant to Section 13 or 15(d)

Senior Unsecured Notes (Summary Of Senior Unsecured Notes) (Details)

v3.21.2
Senior Unsecured Notes (Summary Of Senior Unsecured Notes) (Details) - USD ($)
9 Months Ended
May 06, 2021
Sep. 30, 2021
Dec. 31, 2020
Debt Instrument [Line Items]      
Principal balance outstanding   $ 2,374,947,000 $ 2,801,797,000
Total debt   $ 2,374,947,000 2,801,797,000
4.500% Senior Unsecured Notes Due April 18, 2022 [Member]      
Debt Instrument [Line Items]      
Interest rate of senior unsecured notes   4.50%  
Maturity date of the senior unsecured notes   Apr. 18, 2022  
3.150% Senior Unsecured Notes, Due May 15, 2023 [Member]      
Debt Instrument [Line Items]      
Interest rate of senior unsecured notes   3.15%  
Maturity date of the senior unsecured notes   May 15, 2023  
Senior Unsecured Notes [Member]      
Debt Instrument [Line Items]      
Principal balance outstanding     575,000,000
Adjustment for unamortized debt discount     (1,504,000)
Unamortized deferred financing costs     (843,000)
Total debt     572,653,000
Extinguishment of debt $ 24,200,000    
Senior Unsecured Notes [Member] | 4.500% Senior Unsecured Notes Due April 18, 2022 [Member]      
Debt Instrument [Line Items]      
Principal balance outstanding     300,000,000
Senior Unsecured Notes [Member] | 3.150% Senior Unsecured Notes, Due May 15, 2023 [Member]      
Debt Instrument [Line Items]      
Principal balance outstanding     $ 275,000,000