XML 66 R52.htm IDEA: XBRL DOCUMENT v3.20.4
Notes Payable (Narrative) (Details)
 3 Months Ended 12 Months Ended
Oct. 01, 2020
USD ($)
Dec. 31, 2020
USD ($)
yr
Dec. 31, 2020
USD ($)
yr
Dec. 31, 2019
USD ($)
Dec. 31, 2018
USD ($)
Apr. 16, 2020
USD ($)
Oct. 01, 2019
USD ($)
Debt Instrument, Unamortized Discount (Premium) and Debt Issuance Costs, Net   $ 23,400,000 $ 23,400,000 $ 19,900,000      
Current Fiscal Year End Date     --12-31        
Unsecured Debt   3,166,625,000 $ 3,166,625,000 2,524,099,000      
Total notes payable [1]   3,166,600,000 3,166,600,000 2,524,100,000      
Loss on early retirement of debt     176,000 11,995,000 $ 0    
Available amount under unsecured credit facility   $ 888,000,000.0 $ 888,000,000.0        
Weighted average interest rate on floating rate debt [2]   3.60% 3.60%        
Weighted average maturity of indebtedness (including unsecured credit facility and unsecured short-term borrowings) (in years) | yr   8.4 8.4        
Letter Of Credit [Member]              
Maximum Ability to Issue Letters of Credit Under Unsecured Credit Facility   $ 50,000,000 $ 50,000,000        
Outstanding balance under credit facility   12,000,000.0 12,000,000.0        
Commercial Banks [Member]              
Unsecured Debt   39,700,000 39,700,000 143,700,000      
Commercial Banks [Member] | Unsecured Credit Facility [Member]              
Unsecured Debt   0 0 44,000,000.0      
Senior Unsecured Notes [Member]              
Unsecured Debt   $ 3,126,900,000 $ 3,126,900,000 2,380,400,000      
2.70% Term loan Due 2022 | Commercial Banks [Member]              
Unsecured Debt $ 40,000,000.0     $ 99,700,000      
Notes payable, effective interest rate   1.15% 1.15% 2.70%      
2.70% Term loan Due 2022 | Unsecured Debt [Member]              
Repayments of Unsecured Debt $ 100,000,000.0            
3.74% Notes Due 2028 | Senior Unsecured Notes [Member]              
Unsecured Debt   $ 397,300,000 $ 397,300,000 $ 396,700,000      
Debt Instrument, Maturity Date     Oct. 15, 2028        
Notes payable, effective interest rate       3.74% 3.74%    
Unsecured Credit Facility [Member]              
Value not exceeding the amount available under the unsecured credit facility     $ 450,000,000        
Line of Credit Facility, Maximum Borrowing Capacity   900,000,000 $ 900,000,000        
Terms Of Bid Rate Loans     180 days        
Floating Rate Notes Payable [Member]              
Total notes payable   $ 39,700,000 $ 39,700,000 $ 143,700,000      
Weighted average interest rate on floating rate debt   1.90% 1.90% 2.70%      
3.67% Notes due 2029 | Senior Unsecured Notes [Member]              
Unsecured Debt [3]   $ 594,300,000 $ 594,300,000 $ 593,700,000      
Debt Instrument, Maturity Date     Jul. 01, 2029        
Notes payable, effective interest rate       3.67%      
3.41% Notes due 2049 | Senior Unsecured Notes [Member]              
Unsecured Debt   $ 296,700,000 $ 296,700,000 $ 296,600,000      
Debt Instrument, Maturity Date     Nov. 01, 2049        
Notes payable, effective interest rate   3.41% 3.41% 3.41%      
4.78% Notes Due 2021 | Senior Unsecured Notes [Member]              
Unsecured Debt             $ 250,000,000
Notes payable, effective interest rate             4.78%
Secured Notes 4.38% Fixed Rate Mortgage Note Due 2045 [Member] | Secured Debt [Member]              
Secured Debt             $ 45,300,000
Notes payable, effective interest rate             4.38%
Unsecured notes 2.80% due 2030 [Member] [Member] | Senior Unsecured Notes [Member]              
Debt Instrument, Face Amount           $ 750,000,000  
Discounted notes payable face amount   99.929%          
Debt Instrument, Interest Rate, Stated Percentage           2.80%  
Proceeds from Issuance of Debt   $ 743,100,000          
Debt Instrument, Interest Rate During Period   2.91%          
3.15% Notes Due 2022 | Senior Unsecured Notes [Member]              
Unsecured Debt   $ 348,600,000 $ 348,600,000 $ 348,000,000.0      
Debt Instrument, Maturity Date     Dec. 15, 2022        
Notes payable, effective interest rate   3.15% 3.15% 3.15%      
[1] Unamortized debt discounts and debt issuance costs of $23.4 million and $19.9 million are included in senior unsecured notes payable as of December 31, 2020 and 2019, respectively.
[2] Includes the effects of the applicable settled forward interest rate swaps.
[3] The 2029 Notes have an effective annual interest rate of approximately 3.84% through June 2026, which includes the effect of a settled forward interest rate swap, and approximately 3.28% thereafter, for an all-in average effective rate of approximately 3.67%.