COMMITMENTS AND CONTINGENCIES (Details) $ in Thousands	Oct. 31, 2025 USD ($) home	Sep. 30, 2025 USD ($) community
Real estate properties
Number of communities \| community		168
Costs Incurred to Date		$ 182,256
UDR's Remaining Commitment		120,344
Loss contingency accrual
Contingency liabilities		0
Real estate technology and sustainability investments
Real estate properties
Costs Incurred to Date		129,507
UDR's Remaining Commitment		$ 39,493
Wholly owned - under development
Real estate properties
Number of communities \| community		1
Costs Incurred to Date		$ 52,749
UDR's Remaining Commitment		$ 80,851
Home operating community located in Woodbridge \| Subsequent Event
Real estate properties
Number of apartment homes agreed to acquire \| home	406
Contract to purchase	$ 147,000
Deposit on purchase	$ 3,000

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- Definition

The amount of deposit made on purchase commitment.

+ References

No definition available.

+ Details

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- Definition

Number of properties agreed to acquire by the entity under the purchase commitment contract.

+ References

No definition available.

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- Definition

Amount of loss contingency liability.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 450
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-Name Accounting Standards Codification
-Section 50
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- Definition

The number of real estate properties owned as of the balance sheet date.

+ References

No definition available.

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- Definition

Minimum amount to be expended to satisfy the terms of arrangements in which the entity has agreed to expend funds to procure goods or services, excluding long-term purchase commitments or unconditional purchase obligations.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition

Minimum amount of purchase arrangement in which the entity has agreed to expend funds to procure goods or services from a supplier.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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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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No definition available.

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