Consolidated Statements of Equity - USD ($) $ in Thousands	Simon Property Group, L.P. Simon (Managing General Partner)	Simon Property Group, L.P. Limited Partners	Simon Property Group, L.P. Preferred Stock	Simon Property Group, L.P. Noncontrolling Interests	Simon Property Group, L.P.	Preferred Stock	Common Stock	Accumulated Other Comprehensive Income (Loss)	Capital in Excess of Par Value	Accumulated Deficit	Common Stock Held in Treasury	Noncontrolling Interests	Total
Increase (Decrease) in Stockholders' Equity
Cumulative effect of accounting change										$ 7,264			$ 7,264
Balance at Dec. 31, 2017						$ 43,077	$ 32	$ (110,453)	$ 9,614,748	(4,782,173)	$ (1,079,063)	$ 552,596	4,238,764
Balance at Dec. 31, 2017	$ 3,643,091	$ 548,858	$ 43,077	$ 3,738	$ 4,238,764
Increase (Decrease) in Stockholders' Equity
Exchange of limited partner units (24,000 and 6,000 common shares respectively in three months ended March 2019 and 2018, Note 8)									70			(70)
Series J preferred stock premium amortization			(83)		(83)	(83)							(83)
Limited partner units exchanged to units	70	(70)
Stock incentive program (236 common shares, net)									(37)		37
Redemption of limited partner units (774 and 40,503 units for the three months ended March 2019 and 2018 respectively)	(5,793)	(474)			(6,267)				(5,793)			(474)	(6,267)
Amortization of stock incentive	2,060				2,060				2,060				2,060
Treasury stock purchase (46,377 and 1,473,588 shares for the three months ended March 2019 and 2018 respectively)											(227,901)		(227,901)
Treasury unit purchase (46,377 and 1,473,588 units for the three months ended March 2019 and 2018 respectively)	(227,901)				(227,901)
Long-term incentive performance units												8,307	8,307
Long-term incentive performance units		8,307			8,307
Issuance of unit equivalents and other	(15,208)			24	(15,184)				3	(14,935)	(276)	24	(15,184)
Adjustment to limited partners' interest from change in ownership in the Operating Partnership	36,221	(36,221)							36,221			(36,221)
Distributions to common stockholders and limited partners, excluding Operating Partnership preferred interests										(606,086)		(91,523)	(697,609)
Distributions to other noncontrolling interest partners												(489)	(489)
Distributions to limited partners, excluding preferred interests classified as temporary equity	(605,252)	(91,523)	(834)	(489)	(698,098)
Other comprehensive income	7,706	1,104			8,810			7,706				1,104	8,810
Net income, excluding $479 and $479 attributable to preferred interests in the Operating Partnership during three months ended March 2019 and 2018, respectively and $1,065 and $619 attributable to noncontrolling redeemable interests in properties in three months ended March 2019 and 2018)	620,654	93,649	834	527	715,664					621,488		94,176	715,664
Balance at Mar. 31, 2018						42,994	32	(102,747)	9,647,272	(4,774,442)	(1,307,203)	527,430	4,033,336
Balance at Mar. 31, 2018	3,462,912	523,630	42,994	3,800	4,033,336
Increase (Decrease) in Stockholders' Equity
Cumulative effect of accounting change	7,264				7,264
Balance at Dec. 31, 2018						42,748	32	(126,017)	9,700,418	(4,893,069)	(1,427,431)	500,275	3,796,956
Balance at Dec. 31, 2018	3,253,933	492,877	42,748	7,398	3,796,956
Increase (Decrease) in Stockholders' Equity
Exchange of limited partner units (24,000 and 6,000 common shares respectively in three months ended March 2019 and 2018, Note 8)									253			(253)
Series J preferred stock premium amortization			(82)		(82)	(82)							(82)
Limited partner units exchanged to units	253	(253)
Redemption of limited partner units (774 and 40,503 units for the three months ended March 2019 and 2018 respectively)	(127)	(8)			(135)				(127)			(8)	(135)
Amortization of stock incentive	1,309				1,309				1,309				1,309
Treasury stock purchase (46,377 and 1,473,588 shares for the three months ended March 2019 and 2018 respectively)											(7,628)		(7,628)
Treasury unit purchase (46,377 and 1,473,588 units for the three months ended March 2019 and 2018 respectively)	(7,628)				(7,628)
Long-term incentive performance units												3,701	3,701
Long-term incentive performance units		3,701			3,701
Issuance of unit equivalents and other	(1,756)	(2)			(1,758)				1	(1,507)	(250)	(2)	(1,758)
Adjustment to limited partners' interest from change in ownership in the Operating Partnership	4,167	(4,167)							4,167			(4,167)
Distributions to common stockholders and limited partners, excluding Operating Partnership preferred interests										(634,222)		(96,010)	(730,232)
Distributions to other noncontrolling interest partners												(552)	(552)
Distributions to limited partners, excluding preferred interests classified as temporary equity	(633,388)	(96,010)	(834)	(552)	(730,784)
Other comprehensive income	5,055	775			5,830			5,055				775	5,830
Net income, excluding $479 and $479 attributable to preferred interests in the Operating Partnership during three months ended March 2019 and 2018, respectively and $1,065 and $619 attributable to noncontrolling redeemable interests in properties in three months ended March 2019 and 2018)	548,475	83,076	834	148	632,533					549,309		83,224	632,533
Balance at Mar. 31, 2019						$ 42,666	$ 32	$ (120,962)	$ 9,706,021	$ (4,979,489)	$ (1,435,309)	$ 486,983	$ 3,699,942
Balance at Mar. 31, 2019	$ 3,170,293	$ 479,989	$ 42,666	$ 6,994	$ 3,699,942