Percentage of interest acquired in an asset acquisition.

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Amount of real estate investment property and lease intangible assets.

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Represents the number of luxury outlets acquired.

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Number of regional , super regional and outlet malls.

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The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets.

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- Definition

Amount of consideration transferred in asset acquisition. Includes, but is not limited to, cash, liability incurred by acquirer, and equity interest issued by acquirer.

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Number of shares of equity interest issued or issuable by acquirer as part of consideration transferred in business combination.

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Percentage of voting equity interest acquired in business combination.

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Indicates line item in statement of income or comprehensive income that includes gain from remeasurement of acquisition-date fair value of equity interest in acquiree held by acquirer immediately before acquisition date in business combination achieved in stages.

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Amount of acquiree's earnings (loss) since acquisition date of business combination included in consolidated statement of income.

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Amount of acquiree's revenue since acquisition date of business combination included in consolidated statement of income.

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Percentage of equity in the acquiree held by the acquirer immediately before the acquisition date in a business combination.

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Amount of gain from remeasurement of acquisition-date fair value of equity interest in acquiree held by acquirer immediately before acquisition date in business combination achieved in stages.

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The cash inflow associated with the acquisition of business during the period (for example, cash that was held by the acquired business).

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- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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The interest rate applicable to the portion of the carrying amount of long-term borrowings outstanding as of the balance sheet date, including current maturities, which accrues interest at a set, unchanging rate.

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The portion of the carrying amount of long-term borrowings outstanding as of the balance sheet date, including current maturities, which accrues interest at a set, unchanging rate.

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Amount of real estate investment property which may include the following: (1) land available-for-sale; (2) land available-for-development; (3) investments in building and building improvements; (4) tenant allowances; (5) developments in-process; (6) rental properties; and (7) other real estate investments.

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Real Estate Acquisitions and Dispositions (Details) shares in Thousands, $ in Thousands						3 Months Ended
	Nov. 17, 2025 USD ($)	Oct. 31, 2025 property shares	Jun. 27, 2025 USD ($)	Apr. 01, 2025 USD ($)	Jan. 30, 2025 USD ($) property	Mar. 31, 2026 USD ($)	Dec. 31, 2025 USD ($)
Acquisitions
Investment properties, at cost						$ 50,936,227	$ 50,946,067
Simon Property Group, L.P
Acquisitions
Investment properties, at cost						50,936,227	50,946,067
TRG
Acquisitions
Ownership interest (as a percent)		88.00%
The Mall Firenze and The Mall Sanremo
Acquisitions
Asset acquisition interest acquired (as a percent)					100.00%
Acquisition price					$ 392,400
Investment properties, at cost					413,500
Cash acquired					$ 25,300
Number of luxury outlets acquired \| property					2
Brickell City Centre Property
Acquisitions
Acquisition price			$ 497,700
Cash acquired			24,000
Investment property and lease intangible assets			$ 544,600
Brickell City Centre Retail
Acquisitions
Asset acquisition interest acquired (as a percent)			75.00%
Brickell City Centre Parking
Acquisitions
Asset acquisition interest acquired (as a percent)			100.00%
Briarwood Mall
Acquisitions
Asset acquisition interest acquired (as a percent)				50.00%
Acquisition price				$ 9,200
Investment properties, at cost				168,600
Cash acquired				14,700
Phillips Place
Acquisitions
Asset acquisition interest acquired (as a percent)	100.00%
Acquisition price	$ 143,800
Investment properties, at cost	$ 133,300
Mortgage bearing 3.29% Interest \| Briarwood Mall
Acquisitions
Fixed rate debt				$ 165,000
Fixed rate of interest				3.29%
TRG
Acquisitions
Ownership interests acquired (as a percent)		12.00%
Number of regional, super regional and outlet malls \| property		22
Business combination, step acquisition, non-cash gain							$ 2,858,000
Business Combination, Achieved in Stages, Preacquisition Equity Interest in Acquiree, Remeasurement, Gain, Statement of Income or Comprehensive Income [Extensible Enumeration]							Acquisition Of Controlling Interest Sale Or Disposal Of Or Recovery On Assets And Interests In Unconsolidated Entities Gain Or Loss And Impairment Net
Business combination, step acquisition, Percentage		88.00%
Business combination, total consolidated revenue						186,700
Business combination, Consolidated net loss						34,900
Amount of amortization expenses						$ 34,000
TRG \| Simon Property Group, L.P
Acquisitions
Number of units issued in connection with acquisition \| shares		5,060
TRG \| Consolidated properties
Acquisitions
Number of regional, super regional and outlet malls \| property		11
TRG \| Unconsolidated properties
Acquisitions
Number of regional, super regional and outlet malls \| property		11