Significant Accounting Policies - Reclassification Out Of AOCI, Simon Property Group, L.P. (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021	Dec. 31, 2021
Significant Accounting Policies
Total accumulated other comprehensive income (loss)	$ (173,900)		$ (175,100)
Gain on acquisition of controlling interest, sale or disposal of, or recovery on, assets and interests in unconsolidated entities and impairment, net	1,491	$ 93,057
Interest expense	(185,159)	(202,016)
Loss on extinguishment of debt		(2,959)
Net Income attributable to Common Stockholders - Basic	426,630	445,860
Simon Property Group, L.P.
Significant Accounting Policies
Total accumulated other comprehensive income (loss)	(198,900)		$ (200,200)
Gain on acquisition of controlling interest, sale or disposal of, or recovery on, assets and interests in unconsolidated entities and impairment, net	1,491	93,057
Interest expense	(185,159)	(202,016)
Loss on extinguishment of debt		(2,959)
Net Income attributable to Common Stockholders - Basic	487,993	510,085
Currency translation adjustments. | Amount reclassified from accumulated other comprehensive income (loss)
Significant Accounting Policies
Net Income attributable to Common Stockholders - Basic		4,948
Currency translation adjustments. | Simon Property Group, L.P. | Amount reclassified from accumulated other comprehensive income (loss)
Significant Accounting Policies
Gain on acquisition of controlling interest, sale or disposal of, or recovery on, assets and interests in unconsolidated entities and impairment, net		5,660
Accumulated derivative gains (losses), net | Amount reclassified from accumulated other comprehensive income (loss)
Significant Accounting Policies
Net Income attributable to Common Stockholders - Basic	338	422
Accumulated derivative gains (losses), net | Simon Property Group, L.P. | Amount reclassified from accumulated other comprehensive income (loss)
Significant Accounting Policies
Interest expense	$ 387	$ 483