Per Share and Per Unit Data (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Per Share And Per Unit Data
Net Income attributable to Common Stockholders - Basic	$ 548,475	$ 620,654
Net Income attributable to Common Stockholders - Diluted	$ 548,475	$ 620,654
Weighted Average Shares Outstanding — Basic and Diluted	308,978,053	310,583,643
Simon Property Group, L.P.
Per Share And Per Unit Data
Net Income attributable to Common Stockholders - Basic	$ 631,551	$ 714,303
Net Income attributable to Common Stockholders - Diluted	$ 631,551	$ 714,303
Weighted Average Shares Outstanding — Basic and Diluted	355,778,250	357,446,988