Equity - Changes in Equity, Simon Property Group, Inc. (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2017 USD ($)
Increase (Decrease) in Stockholders' Equity
Balance	$ 4,959,912
Treasury stock purchase	(151,690)
LTIP Units	14,705
Purchase and disposition of noncontrolling interests, net and other	(27,899)
Distributions to common shareholders and limited partners, excluding Operating Partnership preferred interests	(631,427)
Distributions to noncontrolling other interest holders	(1,315)
Comprehensive income, excluding $479 attributable to preferred interests in the Operating Partnership and a $919 loss attributable to noncontrolling redeemable interests in properties	566,719
Balance	4,729,005
Comprehensive income attributable to preferred interests	479
Comprehensive loss attributable to noncontrolling redeemable interests in properties	919
Preferred Stock or Units
Increase (Decrease) in Stockholders' Equity
Balance	43,405
Purchase and disposition of noncontrolling interests, net and other	(82)
Balance	43,323
Common Stock
Increase (Decrease) in Stockholders' Equity
Balance	32
Balance	32
Accumulated Other Comprehensive Income (Loss)
Increase (Decrease) in Stockholders' Equity
Balance	(114,126)
Comprehensive income, excluding $479 attributable to preferred interests in the Operating Partnership and a $919 loss attributable to noncontrolling redeemable interests in properties	13,283
Balance	(100,843)
Capital in Excess of Par Value
Increase (Decrease) in Stockholders' Equity
Balance	9,523,086
Exchange of limited partner units for common shares	12
Purchase and disposition of noncontrolling interests, net and other	1,995
Adjustment to limited partners' interest from change in ownership in the Operating Partnership	33,235
Balance	9,558,328
Accumulated Deficit
Increase (Decrease) in Stockholders' Equity
Balance	(4,459,387)
Purchase and disposition of noncontrolling interests, net and other	(29,699)
Distributions to common shareholders and limited partners, excluding Operating Partnership preferred interests	(548,521)
Comprehensive income, excluding $479 attributable to preferred interests in the Operating Partnership and a $919 loss attributable to noncontrolling redeemable interests in properties	478,570
Balance	(4,559,037)
Common Stock Held in Treasury
Increase (Decrease) in Stockholders' Equity
Balance	(682,562)
Treasury stock purchase	(151,690)
Purchase and disposition of noncontrolling interests, net and other	(284)
Balance	(834,536)
Noncontrolling Interests
Increase (Decrease) in Stockholders' Equity
Balance	649,464
Exchange of limited partner units for common shares	(12)
LTIP Units	14,705
Purchase and disposition of noncontrolling interests, net and other	171
Adjustment to limited partners' interest from change in ownership in the Operating Partnership	(33,235)
Distributions to common shareholders and limited partners, excluding Operating Partnership preferred interests	(82,906)
Distributions to noncontrolling other interest holders	(1,315)
Comprehensive income, excluding $479 attributable to preferred interests in the Operating Partnership and a $919 loss attributable to noncontrolling redeemable interests in properties	74,866
Balance	$ 621,738