Significant Accounting Policies - Reclassification Out Of AOCI, Simon Property Group, L.P. (Details) - USD ($) $ in Thousands |
3 Months Ended | 9 Months Ended | |||
|---|---|---|---|---|---|
Sep. 30, 2026 |
Sep. 30, 2025 |
Sep. 30, 2026 |
Sep. 30, 2025 |
Dec. 31, 2025 |
|
| Summary of Significant Accounting Policies | |||||
| Total accumulated other comprehensive income (loss) | $ (234,100) | $ (234,100) | $ (278,300) | ||
| Interest expense | (287,590) | $ (242,790) | (844,417) | $ (702,509) | |
| Simon Property Group, L.P | |||||
| Summary of Significant Accounting Policies | |||||
| Total accumulated other comprehensive income (loss) | (274,600) | (274,600) | $ (326,000) | ||
| Interest expense | (287,590) | (242,790) | (844,417) | (702,509) | |
| 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 | $ 1,579 | $ 5,118 | $ 4,489 | |