Number of limited partners whose shares are redeemed.

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- Definition

Amount authorized for purchase of share under share repurchase plan. Includes, but is not limited to, repurchase of stock and unit of ownership.

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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.

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- Definition

Aggregate dividends paid during the period for each share of common stock outstanding.

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Aggregate dividends declared during the period for each share of common stock outstanding.

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- Definition

Per unit of ownership amount of cash distributions declared to unit-holder of a limited partnership (LP).

+ References

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Per unit of ownership amount of cash distributions paid to unit-holder of a limited partnership (LP).

+ References

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- Definition

Date the declared dividend will be paid, in YYYY-MM-DD format.

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Date the dividend to be paid was declared, in YYYY-MM-DD format.

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- Definition

Date the holder must own the stock to be entitled to the dividend, in YYYY-MM-DD format.

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No definition available.

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- Definition

Total change in each class of partners' capital accounts during the year due to redemptions and adjustments to redemption value. All partners include general, limited and preferred partners.

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- Definition

The number of units redeemed during the year of each class of partners' capital account. Units represent shares of ownership of the general, limited, and preferred partners.

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- Definition

Period share may be purchased under authorized share repurchase plan, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, repurchase of stock and unit of ownership.

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No definition available.

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Total cost of shares repurchased divided by the total number of shares repurchased.

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Number of shares that have been repurchased during the period and are being held in treasury.

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Equity - Shares or Units Activity (Details) $ / shares in Units, $ in Millions		1 Months Ended	3 Months Ended		12 Months Ended
	Feb. 08, 2024 USD ($)	May 11, 2026 $ / shares	Mar. 31, 2026 USD ($) item $ / shares shares	Mar. 31, 2025 $ / shares shares	Dec. 31, 2025 $ / shares shares	Feb. 05, 2026 USD ($)
Equity
Number of units redeemed (in units) \| shares			6,100	36,291
Shares repurchased (in shares) \| shares			965,296
Common stock dividend per share (in $ per share) \| $ / shares			$ 2.2	$ 2.1
Subsequent Event \| Q2 dividends
Equity
Dividends Payable, Date Declared		May 11, 2026
Dividends Payable, Date of Record		Jun. 09, 2026
Dividends declared per common share (in dollars per share) \| $ / shares		$ 2.25
Dividends Payable, Date to be Paid		Jun. 30, 2026
Common stock repurchase program
Equity
Common stock authorized for repurchase \| $	$ 2,000.0
Period in which common stock is authorized to be repurchased (in years)	2 years
Shares repurchased (in shares) \| shares			273,295		1,246,190
Average share price repurchased (in dollars per share) \| $ / shares			$ 182.95		$ 182.02
New common stock repurchase program
Equity
Common stock authorized for repurchase \| $						$ 2,000.0
Shares repurchased (in shares) \| shares			692,001
Average share price repurchased (in dollars per share) \| $ / shares			$ 181.05
Simon Property Group, L.P.
Equity
Number of units redeemed (in units) \| shares			6,100	36,291
Distributions paid per unit (in dollars per unit) \| $ / shares			$ 2.20	$ 2.10
Simon Property Group, L.P. \| Subsequent Event \| Q2 dividends
Equity
Dividends Payable, Date Declared		May 11, 2026
Dividends Payable, Date of Record		Jun. 09, 2026
Distribution declared per unit (in dollars per share) \| $ / shares		$ 2.25
Dividends Payable, Date to be Paid		Jun. 30, 2026
Simon Property Group, L.P. \| Limited Partner
Equity
Number of units redeemed (in units) \| shares			6,100
Number of limited partners whose common stock redeemed \| item			3
Value of units redeemed \| $			$ 1.2