Percentage points subtracted from the reference rate to compute the variable rate on the debt instrument.

No definition available.

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- Definition

Extension period of option on loan

+ References

No definition available.

+ Details

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Balance Type:	na
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- Definition

Maximum borrowing capacity the credit facility could be adjusted to per agreement.

+ References

No definition available.

+ Details

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Namespace Prefix:	udr_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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- Definition

Term of notes receivable extension options.

+ References

No definition available.

+ Details

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Balance Type:	na
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- Definition

Number of extension options for notes receivable.

+ References

No definition available.

+ Details

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- Definition

Number of Extensions of loan

+ References

No definition available.

+ Details

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- Definition

Summary of short-term bank borrowings under UDR's bank credit facility.

+ References

No definition available.

+ Details

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Namespace Prefix:	udr_
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- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Indicates type of variable interest rate on debt instrument.

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Period Type:	duration

- Definition

Average fixed interest rate related to the group of interest rate derivatives.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Nominal or face amount used to calculate payment on derivative.

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- Definition

The number of derivative instruments of a particular group held by the entity.

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- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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Balance Type:	credit
Period Type:	instant

- Definition

Average amount borrowed under the credit facility during the period.

+ References

No definition available.

+ Details

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Balance Type:	credit
Period Type:	duration

- Definition

The fee, expressed as a percentage of the line of credit facility, for the line of credit facility regardless of whether the facility has been used.

+ References

No definition available.

+ Details

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Data Type:	dtr-types:percentItemType
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- Definition

The effective interest rate at the end of the reporting period.

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- Definition

The effective interest rate during the reporting period.

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Period Type:	duration

- Definition

Maximum amount borrowed under the credit facility at any time during the period.

+ References

No definition available.

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

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Namespace Prefix:	us-gaap_
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SECURED AND UNSECURED DEBT, NET - Credit Facilities (Details) $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2026 USD ($) item loan	Dec. 31, 2025 USD ($)	Sep. 30, 2025 USD ($) instrument
Summary of short-term bank borrowings under unsecured commercial bank credit facility
Notional			$ 175,000
Number of interest rate swaps \| instrument			3
All-in weighted average interest rate			4.04%
Revolving Credit Facility
Summary of short-term bank borrowings under unsecured commercial bank credit facility
Total revolving credit facility	$ 1,300,000
Potential maximum available	$ 2,500,000
Number of Extensions of loan \| loan	2
Extension period of option on loan	6 months
Revolving credit facility due 2023 \| Letter of Credit
Summary of short-term bank borrowings under unsecured commercial bank credit facility
Borrowings outstanding	$ 4,300	$ 4,300
Revolving credit facility due 2023 \| Unsecured Debt
Summary of short-term bank borrowings under unsecured commercial bank credit facility
Basis points added to to variable rate	0.775%
Debt Instrument, Variable Interest Rate, Type [Extensible Enumeration]	us-gaap:SecuredOvernightFinancingRateSofrMember
Commitment fee	0.15%
Revolving credit facility due 2023 \| Unsecured Debt \| Minimum
Summary of short-term bank borrowings under unsecured commercial bank credit facility
Basis points added to to variable rate	0.70%
Commitment fee	0.10%
Revolving credit facility due 2023 \| Unsecured Debt \| Maximum
Summary of short-term bank borrowings under unsecured commercial bank credit facility
Basis points added to to variable rate	1.40%
Commitment fee	0.30%
Revolving credit facility due 2023 \| Revolving Credit Facility
Summary of short-term bank borrowings under unsecured commercial bank credit facility
Total revolving credit facility	$ 1,300,000	1,300,000
Weighted average daily borrowings during the period ended	1,500
Maximum daily borrowings during the period ended	$ 135,000
Weighted average interest rate during the period ended	4.40%
Borrowings outstanding	$ 135,000
Interest rate at end of the period	4.40%
Working Capital Credit Facility \| Unsecured Debt
Summary of short-term bank borrowings under unsecured commercial bank credit facility
Number of extension options \| item	2
Term of notes receivable extension options	1 year
Working Capital Credit Facility \| Variable Rate Debt \| Unsecured Debt
Summary of short-term bank borrowings under unsecured commercial bank credit facility
Total revolving credit facility	$ 75,000	75,000
Weighted average daily borrowings during the period ended	17,233	18,403
Maximum daily borrowings during the period ended	$ 47,811	$ 62,622
Weighted average interest rate during the period ended	4.40%	5.10%
Borrowings outstanding	$ 9,553	$ 26,381
Interest rate at end of the period	4.40%	4.40%
Basis points added to to variable rate	0.775%
Working Capital Credit Facility \| Variable Rate Debt \| Unsecured Debt \| Minimum
Summary of short-term bank borrowings under unsecured commercial bank credit facility
Basis points added to to variable rate	0.70%
Working Capital Credit Facility \| Variable Rate Debt \| Unsecured Debt \| Maximum
Summary of short-term bank borrowings under unsecured commercial bank credit facility
Basis points added to to variable rate	1.40%
Term Loan due September 2023 \| Unsecured Debt
Summary of short-term bank borrowings under unsecured commercial bank credit facility
Basis points added to to variable rate	0.85%
Debt Instrument, Variable Interest Rate, Type [Extensible Enumeration]	us-gaap:SecuredOvernightFinancingRateSofrMember
Term Loan due September 2023 \| Unsecured Debt \| Minimum
Summary of short-term bank borrowings under unsecured commercial bank credit facility
Basis points added to to variable rate	0.75%
Term Loan due September 2023 \| Unsecured Debt \| Maximum
Summary of short-term bank borrowings under unsecured commercial bank credit facility
Basis points added to to variable rate	1.60%
Term Loan due January 2029
Summary of short-term bank borrowings under unsecured commercial bank credit facility
Total revolving credit facility	$ 350,000
Term Loan due January 2029 \| Unsecured Debt
Summary of short-term bank borrowings under unsecured commercial bank credit facility
Number of extension options \| item	2
Term of notes receivable extension options	1 year
Basis point subtracted from variable rate for company receiving green building certifications	5.00%