v3.26.1
Fair Value Measurements (Tables)
12 Months Ended
Dec. 31, 2025
SIMON PROPERTY GROUP AND ADOPTING ENTITIES MATCHING SAVINGS PLAN  
Fair Value Measurements  
Schedule of fair value hierarchy of plan's assets

  ​ ​ ​

Assets at Fair Value as of December 31, 2025

  ​ ​ ​

Level 1

  ​ ​ ​

Level 2

  ​ ​ ​

Level 3

  ​ ​ ​

Total

Common Stock

$

35,292,847

$

$

$

35,292,847

Common/collective trust funds

 

633,646,907

 

 

 

633,646,907

Total assets at fair value

$

668,939,754

$

$

$

668,939,754

  ​ ​ ​

Assets at Fair Value as of December 31, 2024

  ​ ​ ​

Level 1

  ​ ​ ​

Level 2

  ​ ​ ​

Level 3

  ​ ​ ​

Total

Common Stock

$

33,957,609

$

$

$

33,957,609

Common/collective trust funds

 

558,765,242

 

 

 

558,765,242

Total assets at fair value

$

592,722,851

$

$

$

592,722,851