Description of the Plan (Details) - SIMON PROPERTY GROUP AND ADOPTING ENTITIES MATCHING SAVINGS PLAN	12 Months Ended
Dec. 31, 2025 USD ($) age item	Dec. 31, 2024 USD ($)
Description of the Plan
Percentage of ownership in entity	85.40%	86.50%
Minimum service period for Plan eligibility	60 days
Minimum age for Plan eligibility \| age	21
Minimum amount of compensation eligible for participant contribution (as a percent)	1.00%
Maximum amount of compensation eligible for participant contribution (as a percent)	50.00%
Participant's deferral rate (as a percent)	3.00%
Employee contribution automatic increase per year (as a percent)	1.00%
Employee contribution automatic increase, threshold (as a percent)	10.00%
Minimum service period for receiving employer contribution	1 year
Service period for profit sharing eligibility (in hours) \| item	1,000
Discretionary profit-sharing contributions, net of forfeitures	$ 2,874,044	$ 2,736,661
Unallocated participant forfeitures	161,849	$ 116,982
Forfeitures used to reduce employer contributions	$ 170,222
First portion of salary deductions
Description of the Plan
Employer matching contribution (as a percent)	100.00%
Participant compensation matched (as a percent)	3.00%
Second portion of salary deductions
Description of the Plan
Employer matching contribution (as a percent)	50.00%
Participant compensation matched (as a percent)	2.00%

Represents the minimum service period for receiving the employer contribution under (employee benefit plan (EBP)).

No definition available.

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- Definition

Amount of discretionary contributions made by an employer to a defined contribution plan.

+ References

No definition available.

+ Details

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- Definition

Threshold percent of contribution for increase in pretax annual compensation that participant in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)), contributes to total pretax annual compensation.

+ References

No definition available.

+ Details

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- Definition

Represents the minimum age criteria for plan eligibility under (employee benefit plan (EBP)).

+ References

No definition available.

+ Details

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- Definition

Represents the minimum service period for plan eligibility under (employee benefit plan (EBP)).

+ References

No definition available.

+ Details

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- Definition

Percentage of automatic increase per year in pretax annual compensation that participant in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)), contributes to total pretax annual compensation.

+ References

No definition available.

+ Details

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- Definition

Percentage of minimum pretax annual compensation that participant in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)), is permitted to contribute to total pretax annual compensation.

+ References

No definition available.

+ Details

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- Definition

Represents the minimum service period expressed in hours, for profit sharing eligibility under (employee benefit plan (EBP)).

+ References

No definition available.

+ Details

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- Definition

Represents the percentage of controlling ownership in entity.

+ References

No definition available.

+ Details

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 962
-SubTopic 205
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478416/962-205-50-1

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- Definition

Percentage of employer matching contribution on eligible participant contribution to employee stock purchase, saving, or similar plan (employee benefit plan (EBP)).

+ References

+ Details

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- Definition

Percentage of participant compensation eligible for employer matching contribution for participant in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)).

+ References

+ Details

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- Definition

Amount of plan asset, in forfeited nonvested account, no longer allocated to participant in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)).

+ References

+ Details

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- Definition

Amount of decrease in forfeited nonvested account of employee stock purchase, saving, or similar plan (employee benefit plan (EBP)) from employer contribution.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 962
-SubTopic 325
-Name Accounting Standards Codification
-Section 55
-Paragraph 17
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478873/962-325-55-17

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 962
-SubTopic 205
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (j)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478416/962-205-50-1

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 962
-SubTopic 205
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.6A-04(5)(c))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477804/962-205-S99-1

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- Definition

Percentage of eligible compensation contributed for participant automatically enrolled in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)).

+ References

+ Details

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- Definition

Percentage of maximum pretax annual compensation that participant in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)), is permitted to contribute to total pretax annual compensation.

+ References

+ Details

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