v3.26.1
Significant Accounting Policies - Reclassification Out Of AOCI, Simon Property Group, L.P. (Details) - USD ($)
$ in Thousands
3 Months Ended 6 Months Ended
Jun. 30, 2026
Jun. 30, 2025
Jun. 30, 2026
Jun. 30, 2025
Dec. 31, 2025
Summary of Significant Accounting Policies          
Total accumulated other comprehensive income (loss) $ (286,000)   $ (286,000)   $ (278,300)
Interest expense (281,164) $ (232,724) (556,826) $ (459,720)  
Simon Property Group, L.P          
Summary of Significant Accounting Policies          
Total accumulated other comprehensive income (loss) (335,300)   (335,300)   $ (326,000)
Interest expense (281,164) (232,724) (556,826) (459,720)  
Accumulated derivative gains (losses), net | Simon Property Group, L.P | Amount reclassified from accumulated other comprehensive income (loss)          
Summary of Significant Accounting Policies          
Interest expense $ 1,706 $ 1,455 $ 3,412 $ 2,910