Per Share and Per Unit Data (Details) - USD ($) $ / shares in Units, $ in Thousands			3 Months Ended		6 Months Ended
	Aug. 02, 2021	Jun. 21, 2021	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020	Dec. 31, 2020
Per Share And Per Unit Data
Net Income attributable to Common Stockholders - Basic			$ 617,257	$ 254,213	$ 1,063,117	$ 691,818
Net Income attributable to Common Stockholders - Diluted			$ 617,257	$ 254,213	$ 1,063,117	$ 691,818
Weighted Average Shares Outstanding - Basic and Diluted			328,594,136	305,882,326	328,554,537	306,193,205
Dividends
Dividends declared per common share (in dollars per share)	$ 1.50	$ 1.40
Dividend payable			$ 527,508		$ 527,508		$ 486,922
Simon Property Group, L.P.
Per Share And Per Unit Data
Net Income attributable to Common Stockholders - Basic			706,087	$ 292,863	1,216,172	$ 797,125
Net Income attributable to Common Stockholders - Diluted			$ 706,087	$ 292,863	$ 1,216,172	$ 797,125
Weighted Average Shares Outstanding - Basic and Diluted			375,875,290	352,410,392	375,856,079	352,801,176
Dividends
Distribution declared per unit (in dollars per share)		$ 1.40
Dividend payable			$ 527,508		$ 527,508		$ 486,922