v3.26.1
Debt - Narrative (Details)
$ in Thousands, € in Millions
1 Months Ended 3 Months Ended
Mar. 05, 2026
USD ($)
Jan. 15, 2026
USD ($)
Oct. 08, 2025
USD ($)
Sep. 01, 2025
USD ($)
May 12, 2025
EUR (€)
Apr. 25, 2025
USD ($)
Mar. 20, 2025
EUR (€)
Mar. 13, 2025
EUR (€)
Jan. 29, 2025
EUR (€)
May 11, 2026
EUR (€)
Mar. 31, 2026
USD ($)
item
property
Mar. 31, 2026
EUR (€)
item
property
Mar. 31, 2025
USD ($)
Mar. 31, 2026
EUR (€)
property
item
Jan. 13, 2026
USD ($)
Dec. 31, 2025
USD ($)
Oct. 31, 2025
USD ($)
Aug. 19, 2025
USD ($)
Jan. 30, 2025
property
Indebtedness                                      
Long-term debt                     $ 28,247,682         $ 28,430,175      
Amount of debt redeemed                     1,796,818   $ 526,130            
TRG                                      
Indebtedness                                      
Mortgages and unsecured indebtedness                                 $ 3,100,000    
The Mall Firenze and The Mall Sanremo                                      
Indebtedness                                      
Number of luxury outlets acquired | property                                     2
Simon Property Group, L.P.                                      
Indebtedness                                      
Long-term debt                     28,247,682         28,430,175      
Amount of debt redeemed                     1,796,818   $ 526,130            
Exchangeable Debt | Simon Property Group, L.P.                                      
Indebtedness                                      
Long-term debt                     645,500     € 561.1          
Amount of debt converted                     201,400 € 173.5              
Amount of debt redeemed                     90,900 € 78.9              
Exchangeable Debt | Simon Property Group, L.P. | Subsequent Event                                      
Indebtedness                                      
Long-term debt | €                   € 187.6                  
Amount of debt converted | €                   373.5                  
Amount of debt redeemed | €                   € 468.7                  
Unsecured Debt | Unsecured Term Loan | Simon Property Group, L.P.                                      
Indebtedness                                      
Long-term debt                     402,700     € 350.0          
Debt issued | €             € 350.0                        
Interest rate on debt (as a percent)             2.60%                        
Unsecured Debt | Credit Facilities | Simon Property Group, L.P.                                      
Indebtedness                                      
Available borrowing capacity                     7,500,000                
Maximum amount outstanding during period                     460,000                
Credit facility, weighted average amount outstanding                     460,000                
Letters of credit outstanding                     3,100                
Unsecured Debt | Credit Facility | Simon Property Group, L.P.                                      
Indebtedness                                      
Credit facility, amount outstanding                     460,000                
Maximum borrowing capacity $ 5,000,000                   $ 5,000,000                
Additional borrowing capacity 1,000,000                                    
Optional expanded maximum borrowing capacity $ 6,000,000                                    
Debt extension period 1 year                                    
Credit facility, amount repaid | €             € 376.0 € 18.0                      
Amount drawn           $ 155,000     € 376.0                    
Unsecured Debt | Credit Facility | Simon Property Group, L.P. | Fed Funds Effective Rate                                      
Indebtedness                                      
Interest rate (as a percent)                     0.50% 0.50%              
Unsecured Debt | Credit Facility | Simon Property Group, L.P. | Adjusted Term One-Month SOFR                                      
Indebtedness                                      
Interest rate (as a percent)                     1.00% 1.00%              
Unsecured Debt | Credit Facility | Simon Property Group, L.P. | Secured Overnight Financing Rate (SOFR)                                      
Indebtedness                                      
Interest rate (as a percent)                     0.65% 0.65%              
Unsecured Debt | Credit Facility | Minimum | Simon Property Group, L.P.                                      
Indebtedness                                      
Facility fee (in percentage)                     0.10% 0.10%              
Unsecured Debt | Credit Facility | Minimum | Simon Property Group, L.P. | Base Rate                                      
Indebtedness                                      
Interest rate (as a percent)                     0.00% 0.00%              
Unsecured Debt | Credit Facility | Minimum | Simon Property Group, L.P. | Secured Overnight Financing Rate (SOFR) Overnight Index Swap Rate                                      
Indebtedness                                      
Interest rate (as a percent)                     0.625% 0.625%              
Unsecured Debt | Credit Facility | Maximum | Simon Property Group, L.P.                                      
Indebtedness                                      
Facility fee (in percentage)                     0.30% 0.30%              
Unsecured Debt | Credit Facility | Maximum | Simon Property Group, L.P. | Base Rate                                      
Indebtedness                                      
Interest rate (as a percent)                     0.35% 0.35%              
Unsecured Debt | Credit Facility | Maximum | Simon Property Group, L.P. | Secured Overnight Financing Rate (SOFR) Overnight Index Swap Rate                                      
Indebtedness                                      
Interest rate (as a percent)                     1.35% 1.35%              
Unsecured Debt | Supplemental Facility | Simon Property Group, L.P.                                      
Indebtedness                                      
Maximum borrowing capacity                     $ 3,500,000                
Optional expanded maximum borrowing capacity                     $ 4,500,000                
Credit facility, amount repaid     $ 500,000                                
Amount drawn | €         € 500.0                            
Unsecured Debt | Supplemental Facility | Simon Property Group, L.P. | Fed Funds Effective Rate                                      
Indebtedness                                      
Interest rate (as a percent)                     0.50% 0.50%              
Unsecured Debt | Supplemental Facility | Simon Property Group, L.P. | Adjusted Term One-Month SOFR                                      
Indebtedness                                      
Interest rate (as a percent)                     1.00% 1.00%              
Unsecured Debt | Supplemental Facility | Simon Property Group, L.P. | Secured Overnight Financing Rate (SOFR)                                      
Indebtedness                                      
Interest rate (as a percent)                     0.65% 0.65%              
Unsecured Debt | Supplemental Facility | Minimum | Simon Property Group, L.P.                                      
Indebtedness                                      
Facility fee (in percentage)                     0.10% 0.10%              
Unsecured Debt | Supplemental Facility | Minimum | Simon Property Group, L.P. | Base Rate                                      
Indebtedness                                      
Interest rate (as a percent)                     0.00% 0.00%              
Unsecured Debt | Supplemental Facility | Minimum | Simon Property Group, L.P. | Secured Overnight Financing Rate (SOFR)                                      
Indebtedness                                      
Interest rate (as a percent)                     0.625% 0.625%              
Unsecured Debt | Supplemental Facility | Maximum | Simon Property Group, L.P.                                      
Indebtedness                                      
Facility fee (in percentage)                     0.30% 0.30%              
Unsecured Debt | Supplemental Facility | Maximum | Simon Property Group, L.P. | Base Rate                                      
Indebtedness                                      
Interest rate (as a percent)                     0.35% 0.35%              
Unsecured Debt | Supplemental Facility | Maximum | Simon Property Group, L.P. | Secured Overnight Financing Rate (SOFR)                                      
Indebtedness                                      
Interest rate (as a percent)                     1.35% 1.35%              
Unsecured Debt | Commercial Paper | Simon Property Group, L.P.                                      
Indebtedness                                      
Credit facility, amount outstanding                     $ 537,200                
Maximum borrowing capacity                     2,000,000                
Unsecured Debt | U.S Dollar Denominated Notes | Simon Property Group, L.P.                                      
Indebtedness                                      
Credit facility, amount outstanding                     $ 537,200                
Weighted average interest rate (as a percent)                     3.94%     3.94%          
Unsecured Debt | Senior unsecured notes | Simon Property Group, L.P.                                      
Indebtedness                                      
Long-term debt                     $ 18,900,000                
Unsecured Debt | Senior Unsecured Notes 3.30% due 2026 | Simon Property Group, L.P.                                      
Indebtedness                                      
Amount of debt redeemed   $ 800,000                                  
Interest rate on debt (as a percent)   3.30%                                  
Unsecured Debt | Senior Unsecured Notes 4.375 due 2030 | Simon Property Group, L.P.                                      
Indebtedness                                      
Debt issued                                   $ 700,000  
Interest rate on debt (as a percent)                                   4.375%  
Unsecured Debt | Senior Unsecured Notes 5.125 due 2035 | Simon Property Group, L.P.                                      
Indebtedness                                      
Debt issued                                   $ 800,000  
Interest rate on debt (as a percent)                                   5.125%  
Unsecured Debt | Senior Unsecured Notes 3.50 due 2035 | Simon Property Group, L.P.                                      
Indebtedness                                      
Amount of debt redeemed       $ 1,100,000                              
Interest rate on debt (as a percent)       3.50%                              
Unsecured Debt | Senior Unsecured Notes 1.25% due 2025 | Simon Property Group, L.P.                                      
Indebtedness                                      
Amount of debt redeemed | €         € 500.0                            
Unsecured Debt | Senior Unsecured Notes Maturing January 2031 | Simon Property Group, L.P.                                      
Indebtedness                                      
Debt issued                             $ 800,000        
Interest rate on debt (as a percent)                             4.30%        
Secured Debt | Mortgages                                      
Indebtedness                                      
Long-term debt                     $ 8,100,000         $ 8,200,000      
Debt covenants                                      
Number of non-recourse mortgage notes under which the Company and subsidiaries are borrowers | item                     41 41              
Number of properties pledged as collateral | property                     44 44              
Number of cross-defaulted and cross-collateralized mortgage pools | item                     2     2          
Total number of properties pledged as collateral for cross defaulted and cross collateralized mortgages | property                     5     5