v3.26.1
Equity - Temporary Equity (Details)
$ in Thousands
 3 Months Ended 12 Months Ended
Mar. 31, 2026
USD ($)
item
shares
Dec. 31, 2025
USD ($)
shares
Redeemable preferred stock    
Limited partners' preferred interest in the Operating Partnership and noncontrolling redeemable interests $ 264,251 $ 233,306
Simon Property Group, L.P.    
Redeemable preferred stock    
Limited partners' preferred interest in the Operating Partnership and noncontrolling redeemable interests $ 264,251 233,306
7.5% Cumulative Redeemable Preferred Units    
Redeemable preferred stock    
Number of series of units classified into temporary equity | item 1  
Noncontrolling interests redeemable at amounts in excess of fair value $ 0 $ 0
Preferred stock stated dividend rate (as a percent) 7.50% 7.50%
Temporary equity, shares authorized | shares 260,000 260,000
Temporary equity, shares issued | shares 105,373 105,373
Temporary equity, shares outstanding | shares 105,373 105,373
Limited partners' preferred interest in the Operating Partnership and noncontrolling redeemable interests $ 10,537 $ 10,537
7.5% Cumulative Redeemable Preferred Units | Simon Property Group, L.P.    
Redeemable preferred stock    
Number of series of units classified into temporary equity | item 1  
Preferred stock stated dividend rate (as a percent) 7.50% 7.50%
Temporary equity, shares authorized | shares 260,000 260,000
Temporary equity, shares issued | shares 105,373 105,373
Temporary equity, shares outstanding | shares 105,373 105,373
Limited partners' preferred interest in the Operating Partnership and noncontrolling redeemable interests $ 10,537 $ 10,537
Other noncontrolling redeemable interest    
Redeemable preferred stock    
Limited partners' preferred interest in the Operating Partnership and noncontrolling redeemable interests 253,714 222,769
Other noncontrolling redeemable interest | Simon Property Group, L.P.    
Redeemable preferred stock    
Limited partners' preferred interest in the Operating Partnership and noncontrolling redeemable interests $ 253,714 $ 222,769