Investments in Unconsolidated Entities and International Investments - Unconsolidated Property Transactions (Details) - USD ($) $ in Thousands				1 Months Ended	3 Months Ended									12 Months Ended
	Sep. 07, 2023	Dec. 19, 2022	Dec. 20, 2021	Dec. 31, 2022	Dec. 31, 2023	Sep. 30, 2023	Jun. 30, 2023	Mar. 31, 2023	Dec. 31, 2022	Sep. 30, 2022	Jun. 30, 2022	Mar. 31, 2022	Sep. 30, 2021	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Jun. 30, 2021
Investment in Unconsolidated Entities
Payments for acquisitions														$ 65,829	$ 203,364	$ 257,080
Total assets				$ 33,011,274	$ 34,283,495				$ 33,011,274					34,283,495	33,011,274
Total liabilities				29,187,383	30,595,897				29,187,383					30,595,897	29,187,383
Noncontrolling interests				473,128	468,815				473,128					468,815	473,128
Total revenue					1,527,438	$ 1,410,948	$ 1,369,601	$ 1,350,849	1,399,898	$ 1,315,786	$ 1,279,842	$ 1,295,922		5,658,836	5,291,447	5,116,789
Operating income before other items					792,139	694,234	657,925	662,723	684,205	652,196	626,761	620,391		2,807,022	2,583,553	2,413,190
Consolidated net income					859,496	$ 680,762	$ 557,505	$ 519,255	772,748	621,847	$ 569,480	$ 488,310		2,617,018	2,452,385	2,568,707
Gain (loss) on disposal, exchange, or revaluation of equity interests				(10,200)										362,019	121,177	178,672
TRG
Investment in Unconsolidated Entities
Total assets				3,555,686	3,416,630				3,555,686					3,416,630	3,555,686
Total liabilities				4,356,406	4,386,131				4,356,406					4,386,131	4,356,406
Noncontrolling interests				163,293	164,720				163,293					164,720	163,293
Total revenue														695,222	693,835	600,426
Operating income before other items														281,349	254,395	197,074
Consolidated net income														42,910	164,072	97,361
Our share of net income (loss)														32,728	129,065	78,370
Amortization of Excess Investment														113,333	189,629	196,072
Other Platform Investments
Investment in Unconsolidated Entities
Total assets				12,897,980	14,921,120				12,897,980					14,921,120	12,897,980
Total liabilities				10,521,772	11,406,440				10,521,772					11,406,440	10,521,772
Noncontrolling interests				362,652	501,224				362,652					501,224	362,652
Total revenue														13,865,845	14,895,379	14,454,661
Operating income before other items														683,723	972,360	1,550,358
Consolidated net income														239,491	738,255	1,400,632
Our share of net income (loss)														40,002	238,412	402,658
Amortization of Excess Investment														6,740	6,659	7,546
Simon Property Group, L.P.
Investment in Unconsolidated Entities
Payments for acquisitions														65,829	203,364	257,080
Total assets				33,011,274	34,283,495				33,011,274					34,283,495	33,011,274
Total liabilities				29,187,383	$ 30,595,897				29,187,383					30,595,897	29,187,383
Total revenue														5,658,836	5,291,447	5,116,789
Operating income before other items														2,807,022	2,583,553	2,413,190
Consolidated net income														2,617,018	2,452,385	2,568,707
Gain (loss) on disposal, exchange, or revaluation of equity interests														$ 362,019	121,177	$ 178,672
Jamestown
Investment in Unconsolidated Entities
Ownership interest acquired (as a percent)		50.00%
Payments for acquisitions		$ 173,400
TRG
Investment in Unconsolidated Entities
Ownership interest (as a percent)	84.00%				84.00%									84.00%
Ownership interest acquired (as a percent)	4.00%
Payments for acquisitions	$ 199,600
Aggregate investment in ventures				3,074,345	$ 3,049,719				3,074,345					$ 3,049,719	3,074,345
TRG | Series A Cumulative Preferred Shares
Investment in Unconsolidated Entities
Preferred stock stated dividend rate (as a percent)														6.38%
Issuance of preferred units														$ 362,500
TRG | Simon Property Group, L.P.
Investment in Unconsolidated Entities
Number of units issued in connection with acquisition	1,725,000
Aggregate investment in ventures				3,074,345	$ 3,049,719				3,074,345					$ 3,049,719	3,074,345
Eddie Bauer
Investment in Unconsolidated Entities
Aggregate investment in ventures										$ 98,800
Gain (loss) on disposal, exchange, or revaluation of equity interests									159,000
Deferred Taxes				39,700					39,700						39,700
JC Penney
Investment in Unconsolidated Entities
Ownership interest (as a percent)					41.67%									41.67%
SPARC Group
Investment in Unconsolidated Entities
Ownership interest (as a percent)					33.30%	33.30%								33.30%
Gain (loss) on disposal, exchange, or revaluation of equity interests						$ 145,800
Deferred Taxes						$ 36,900
Forever 21 and Brooks Brothers
Investment in Unconsolidated Entities
Aggregate investment in ventures																	$ 102,700
Gain (loss) on disposal, exchange, or revaluation of equity interests													$ 159,800
Deferred Taxes													$ 47,900
ABG
Investment in Unconsolidated Entities
Ownership interest (as a percent)					9.60%	11.70%	11.80%	12.30%						9.60%
Payments for acquisitions			$ 100,000
Aggregate investment in ventures				$ 767,500	$ 733,200				$ 767,500					$ 733,200	$ 767,500
Proceeds from sale or disposal of real estate assets					300,200
Gain (loss) on disposal, exchange, or revaluation of equity interests					10,300	$ 12,400	$ 36,400
Deferred Taxes					2,600	$ 3,100	$ 9,100							$ 2,600
Pre-tax gain			18,800		157,100
Tax expense			$ 8,000		$ 39,300
RGG
Investment in Unconsolidated Entities
Ownership interest (as a percent)					45.00%									45.00%