v3.26.1
Long-Term Debt - Components of Long-Term Debt (Details) - USD ($)
$ in Millions
Jun. 30, 2026
May 27, 2026
Dec. 31, 2025
Long-Term Debt      
Long-term debt principal $ 4,358.5   $ 3,958.5
Net unamortized discount, premium and debt issuance costs (34.1)   (32.2)
Long-term debt carrying amount $ 4,324.4   $ 3,926.3
3.1% notes payable, due 2026      
Long-Term Debt      
Interest rate (as a percent) 3.10%   3.10%
Long-term debt principal $ 350.0   $ 350.0
Net unamortized discount, premium and debt issuance costs (0.1)   (0.4)
Long-term debt carrying amount $ 349.9   $ 349.6
4.111% notes payable, due 2028      
Long-Term Debt      
Interest rate (as a percent) 4.111%   4.111%
Long-term debt principal $ 400.0   $ 400.0
Net unamortized discount, premium and debt issuance costs (7.5)   (9.8)
Long-term debt carrying amount $ 392.5   $ 390.2
3.7% notes payable, due 2029      
Long-Term Debt      
Interest rate (as a percent) 3.70%   3.70%
Long-term debt principal $ 500.0   $ 500.0
Net unamortized discount, premium and debt issuance costs (2.1)   (2.5)
Long-term debt carrying amount $ 497.9   $ 497.5
2.125% notes payable, due 2030      
Long-Term Debt      
Interest rate (as a percent) 2.125%   2.125%
Long-term debt principal $ 600.0   $ 600.0
Net unamortized discount, premium and debt issuance costs (2.0)   (2.2)
Long-term debt carrying amount $ 598.0   $ 597.8
5.375% notes payable, due 2033      
Long-Term Debt      
Interest rate (as a percent) 5.375%   5.375%
Long-term debt principal $ 400.0   $ 400.0
Net unamortized discount, premium and debt issuance costs (3.0)   (3.1)
Long-term debt carrying amount $ 397.0   $ 396.9
6.05% notes payable, due 2036      
Long-Term Debt      
Interest rate (as a percent) 6.05%   6.05%
Long-term debt principal $ 505.6   $ 505.6
Net unamortized discount, premium and debt issuance costs (1.9)   (1.9)
Long-term debt carrying amount $ 503.7   $ 503.7
5.3% notes payable, due 2037      
Long-Term Debt      
Interest rate (as a percent) 5.30%    
Long-term debt principal $ 400.0    
Net unamortized discount, premium and debt issuance costs (5.1)    
Long-term debt carrying amount $ 394.9    
5.3% notes payable, due 2037 | Senior notes      
Long-Term Debt      
Interest rate (as a percent)   5.30%  
Long-term debt issued   $ 400.0  
4.625% notes payable, due 2042      
Long-Term Debt      
Interest rate (as a percent) 4.625%   4.625%
Long-term debt principal $ 300.0   $ 300.0
Net unamortized discount, premium and debt issuance costs (2.6)   (2.6)
Long-term debt carrying amount $ 297.4   $ 297.4
4.35% notes payable, due 2043      
Long-Term Debt      
Interest rate (as a percent) 4.35%   4.35%
Long-term debt principal $ 300.0   $ 300.0
Net unamortized discount, premium and debt issuance costs (2.6)   (2.6)
Long-term debt carrying amount $ 297.4   $ 297.4
4.3% notes payable, due 2046      
Long-Term Debt      
Interest rate (as a percent) 4.30%   4.30%
Long-term debt principal $ 300.0   $ 300.0
Net unamortized discount, premium and debt issuance costs (2.8)   (2.8)
Long-term debt carrying amount $ 297.2   $ 297.2
5.5% notes payable, due 2053      
Long-Term Debt      
Interest rate (as a percent) 5.50%   5.50%
Long-term debt principal $ 300.0   $ 300.0
Net unamortized discount, premium and debt issuance costs (4.2)   (4.2)
Long-term debt carrying amount 295.8   295.8
Mortgages and notes payable | Non-recourse      
Long-Term Debt      
Long-term debt principal 2.9   2.9
Net unamortized discount, premium and debt issuance costs (0.2)   (0.1)
Long-term debt carrying amount $ 2.7   $ 2.8