Significant Accounting Policies - Reclassification Out Of AOCI, Simon Property Group, L.P. (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Significant Accounting Policies
Interest expense	$ (198,202)	$ (219,190)
Gain upon acquisition of controlling interests and sale or disposal of assets and interests in unconsolidated entities, net		22,688
Other Income	61,299	84,250
NET INCOME ATTRIBUTABLE TO COMMON STOCKHOLDERS or UNITHOLDERS	477,736	480,995
Simon Property Group L.P.
Significant Accounting Policies
Interest expense	(198,202)	(219,190)
Gain upon acquisition of controlling interests and sale or disposal of assets and interests in unconsolidated entities, net		22,688
Other Income	61,299	84,250
NET INCOME ATTRIBUTABLE TO COMMON STOCKHOLDERS or UNITHOLDERS	550,006	561,797
Currency translation adjustments, attributable to parent | Amount reclassified from accumulated other comprehensive income (loss)
Significant Accounting Policies
NET INCOME ATTRIBUTABLE TO COMMON STOCKHOLDERS or UNITHOLDERS		(117,027)
Currency translation adjustments, attributable to parent | Simon Property Group L.P. | Amount reclassified from accumulated other comprehensive income (loss)
Significant Accounting Policies
Gain upon acquisition of controlling interests and sale or disposal of assets and interests in unconsolidated entities, net		(136,806)
NET INCOME ATTRIBUTABLE TO COMMON STOCKHOLDERS or UNITHOLDERS		(136,806)
Accumulated derivative gains, attributable to parent | Amount reclassified from accumulated other comprehensive income (loss)
Significant Accounting Policies
NET INCOME ATTRIBUTABLE TO COMMON STOCKHOLDERS or UNITHOLDERS	(2,275)	(2,167)
Accumulated derivative gains, attributable to parent | Simon Property Group L.P. | Amount reclassified from accumulated other comprehensive income (loss)
Significant Accounting Policies
Interest expense	(2,620)	(2,905)
Gain upon acquisition of controlling interests and sale or disposal of assets and interests in unconsolidated entities, net		372
NET INCOME ATTRIBUTABLE TO COMMON STOCKHOLDERS or UNITHOLDERS	$ (2,620)	$ (2,533)