Per Share and Per Unit Data (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Per Share And Per Unit Data
Net Income attributable to Common Stockholders - Basic	$ 547,004	$ 381,990	$ 1,167,658	$ 859,726
Net Income attributable to Common Stockholders - Diluted	$ 547,004	$ 381,990	$ 1,167,658	$ 859,726
Weighted Average Shares Outstanding — Basic and Diluted	309,355,154	311,579,301	309,966,005	312,191,241
Simon Property Group, L.P.
Per Share And Per Unit Data
Net Income attributable to Common Stockholders - Basic	$ 629,822	$ 439,986	$ 1,344,126	$ 989,992
Net Income attributable to Common Stockholders - Diluted	$ 629,822	$ 439,986	$ 1,344,126	$ 989,992
Weighted Average Shares Outstanding — Basic and Diluted	356,181,817	358,865,806	356,810,908	359,494,630