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DEBT, NET (UNITED DOMINION REALTY, L.P.) - Additional Information (Details) |  |  | 1 Months Ended |  |  |  |  |
--- | --- | --- | --- | --- | --- | --- | --- | ---
Jul. 21, 2020 USD ($) | Jul. 14, 2020 USD ($) | Feb. 29, 2020 USD ($) | Jun. 30, 2020 USD ($) | Mar. 31, 2020 USD ($) | Dec. 31, 2019 USD ($) | Oct. 31, 2019 USD ($) | Jul. 31, 2019 USD ($)
Fixed and variable rate debt |  |  |  |  |  |  |  |
Long-term commercial paper |  |  |  | $ 500,000,000.0 |  |  |  |
Borrowings outstanding |  |  |  | 2,900,000 |  | $ 2,900,000 |  |
Commercial Paper |  |  |  |  |  |  |  |
Fixed and variable rate debt |  |  |  |  |  |  |  |
Commercial paper program |  |  |  | $ 185,000,000 |  | $ 300,000,000 |  |
Interest rate at the end of the period |  |  |  | 0.40% |  | 2.00% |  |
Credit facilities | Fixed Rate Debt |  |  |  |  |  |  |  |
Fixed and variable rate debt |  |  |  |  |  |  |  |
Principal outstanding |  |  |  | $ 202,254,000 |  | $ 204,590,000 |  |
Mortgages Note Payable | Fixed Rate Debt |  |  |  |  |  |  |  |
Fixed and variable rate debt |  |  |  |  |  |  |  |
Principal outstanding |  |  |  | 855,585,000 |  | 884,869,000 |  |
Tax-exempt secured notes payable | Variable Rate Debt |  |  |  |  |  |  |  |
Fixed and variable rate debt |  |  |  |  |  |  |  |
Principal outstanding |  |  |  | 27,000,000 |  | 27,000,000 |  |
Term Loan due September 2023 |  |  |  |  |  |  |  |
Fixed and variable rate debt |  |  |  |  |  |  |  |
Senior Notes |  |  |  | 35,000,000 |  | 35,000,000 |  |
3.75% Medium-Term Notes Due July 2024 |  |  |  |  |  |  |  |
Fixed and variable rate debt |  |  |  |  |  |  |  |
Senior Notes |  |  |  | 299,583,000 |  | 299,530,000 |  |
2.10% Medium Term Note Due August 1, 2032 |  |  |  |  |  |  |  |
Fixed and variable rate debt |  |  |  |  |  |  |  |
Interest rate | 2.10% |  |  |  |  |  |  |
Debt | $ 400,000,000.0 |  |  |  |  |  |  |
Price as percentage of principal amount | 99.894 |  |  |  |  |  |  |
4.64% Secured Debt Due in 2023 |  |  |  |  |  |  |  |
Fixed and variable rate debt |  |  |  |  |  |  |  |
Interest rate | 4.64% |  |  |  |  |  |  |
Repayment of debt | $ 245,800,000 |  |  |  |  |  |  |
4.00% Medium-Term Note due October 2025 |  |  |  |  |  |  |  |
Fixed and variable rate debt |  |  |  |  |  |  |  |
Senior Notes |  |  |  | 299,638,000 |  | 299,604,000 |  |
2.95% Medium-Term Note due September 2026 |  |  |  |  |  |  |  |
Fixed and variable rate debt |  |  |  |  |  |  |  |
Senior Notes |  |  |  | 300,000,000 |  | 300,000,000 |  |
3.50 Medium-Term Note due July 2027 |  |  |  |  |  |  |  |
Fixed and variable rate debt |  |  |  |  |  |  |  |
Senior Notes |  |  |  | 299,506,000 |  | 299,471,000 |  |
3.50% Medium-Term Notes Due January 2028 |  |  |  |  |  |  |  |
Fixed and variable rate debt |  |  |  |  |  |  |  |
Senior Notes |  |  |  | 299,106,000 |  | 299,046,000 |  |
3.20% Medium-Term Notes due January 2030 |  |  |  |  |  |  |  |
Fixed and variable rate debt |  |  |  |  |  |  |  |
Guarantor borrowing capacity |  |  |  | 600,000,000 |  |  |  |
Interest rate |  |  | 3.20% |  |  |  | 3.20% | 3.20%
Senior Notes |  |  | $ 600,000,000.0 | 613,099,000 |  | 402,281,000 |  |
Debt |  |  | $ 200,000,000.0 |  |  |  | $ 100,000,000.0 | $ 300,000,000.0
Price as percentage of principal amount |  |  | 105.660 |  |  |  |  |
Medium-Term Notes Due August 2031 |  |  |  |  |  |  |  |
Fixed and variable rate debt |  |  |  |  |  |  |  |
Guarantor borrowing capacity |  |  |  | 400,000,000 |  |  |  |
Debt |  |  |  | 150,000,000.0 |  |  |  |
3.10% senior unsecured notes due 2034 |  |  |  |  |  |  |  |
Fixed and variable rate debt |  |  |  |  |  |  |  |
Guarantor borrowing capacity |  |  |  | 300,000,000 |  |  |  |
United Dominion Realty L.P. | Financial Guarantee |  |  |  |  |  |  |  |
Fixed and variable rate debt |  |  |  |  |  |  |  |
Guarantor borrowing capacity |  |  |  | 1,100,000,000 |  |  |  |
United Dominion Realty L.P. | Unsecured Commercial Bank Credit Facility |  |  |  |  |  |  |  |
Fixed and variable rate debt |  |  |  |  |  |  |  |
Long-term commercial paper |  |  |  | 500,000,000 |  |  |  |
United Dominion Realty L.P. | Mortgages Note Payable |  |  |  |  |  |  |  |
Fixed and variable rate debt |  |  |  |  |  |  |  |
Principal outstanding |  |  |  | $ 72,500,000 |  |  |  |
Interest rate |  |  |  | 3.10% |  |  |  |
United Dominion Realty L.P. | Mortgages Note Payable | Fixed Rate Debt |  |  |  |  |  |  |  |
Fixed and variable rate debt |  |  |  |  |  |  |  |
Principal outstanding |  |  |  | $ 72,500,000 |  | 72,500,000 |  |
United Dominion Realty L.P. | Mortgages Note Payable | Variable Rate Debt | Operating Partnership |  |  |  |  |  |  |  |
Fixed and variable rate debt |  |  |  |  |  |  |  |
Principal outstanding |  |  |  | $ 27,000,000.0 |  |  |  |
Interest rate at the end of the period |  |  |  | 0.85% |  |  |  |
United Dominion Realty L.P. | Tax-exempt secured notes payable | Variable Rate Debt |  |  |  |  |  |  |  |
Fixed and variable rate debt |  |  |  |  |  |  |  |
Principal outstanding |  |  |  | $ 27,000,000 |  | 27,000,000 |  |
United Dominion Realty L.P. | Unsecured Commercial Paper |  |  |  |  |  |  |  |
Fixed and variable rate debt |  |  |  |  |  |  |  |
Borrowings outstanding |  |  |  | 185,000,000.0 |  | $ 300,000,000.0 |  |
United Dominion Realty L.P. | 3.70% Term Notes Due October 2020 |  |  |  |  |  |  |  |
Fixed and variable rate debt |  |  |  |  |  |  |  |
Guarantor borrowing capacity |  |  |  | 300,000,000 |  |  |  |
United Dominion Realty L.P. | Term Loan due September 2023 |  |  |  |  |  |  |  |
Fixed and variable rate debt |  |  |  |  |  |  |  |
Guarantor borrowing capacity |  |  |  | 350,000,000 |  |  |  |
United Dominion Realty L.P. | 3.75% Medium-Term Notes Due July 2024 |  |  |  |  |  |  |  |
Fixed and variable rate debt |  |  |  |  |  |  |  |
Guarantor borrowing capacity |  |  |  |  | $ 300,000,000 |  |  |
United Dominion Realty L.P. | 2.10% Medium Term Note Due August 1, 2032 |  |  |  |  |  |  |  |
Fixed and variable rate debt |  |  |  |  |  |  |  |
Guarantor borrowing capacity | $ 400,000,000.0 |  |  |  |  |  |  |
Interest rate | 2.10% |  |  |  |  |  |  |
Price as percentage of principal amount | 99.894 |  |  |  |  |  |  |
United Dominion Realty L.P. | 4.64% Secured Debt Due in 2023 |  |  |  |  |  |  |  |
Fixed and variable rate debt |  |  |  |  |  |  |  |
Interest rate | 4.64% |  |  |  |  |  |  |
Repayment of debt | $ 245,800,000 |  |  |  |  |  |  |
United Dominion Realty L.P. | 4.00% Medium-Term Note due October 2025 |  |  |  |  |  |  |  |
Fixed and variable rate debt |  |  |  |  |  |  |  |
Guarantor borrowing capacity |  |  |  | 300,000,000 |  |  |  |
United Dominion Realty L.P. | 2.95% Medium-Term Note due September 2026 |  |  |  |  |  |  |  |
Fixed and variable rate debt |  |  |  |  |  |  |  |
Guarantor borrowing capacity |  |  |  | 300,000,000 |  |  |  |
United Dominion Realty L.P. | 3.50 Medium-Term Note due July 2027 |  |  |  |  |  |  |  |
Fixed and variable rate debt |  |  |  |  |  |  |  |
Guarantor borrowing capacity |  |  |  | 300,000,000 |  |  |  |
United Dominion Realty L.P. | Medium-Term note due January 2029 |  |  |  |  |  |  |  |
Fixed and variable rate debt |  |  |  |  |  |  |  |
Guarantor borrowing capacity |  |  |  | 300,000,000 |  |  |  |
Credit facilities |  |  |  |  |  |  |  |
Fixed and variable rate debt |  |  |  |  |  |  |  |
Principal outstanding |  |  |  | $ 202,300,000 |  |  |  |
Cash Tender Offer | 3.75% Medium-Term Notes Due July 2024 |  |  |  |  |  |  |  |
Fixed and variable rate debt |  |  |  |  |  |  |  |
Principal outstanding |  | $ 300,000,000.0 |  |  |  |  |  |
Interest rate |  | 3.75% |  |  |  |  |  |
Tendered value |  | $ 116,900,000 |  |  |  |  |  |
Tendered percentage |  | 39.00% |  |  |  |  |  |
Tender offer consideration per each $1,000 |  | $ 1,101.92 |  |  |  |  |  |
Make-whole amount |  | 24,000,000.0 |  |  |  |  |  |
Cash Tender Offer | United Dominion Realty L.P. | 3.75% Medium-Term Notes Due July 2024 |  |  |  |  |  |  |  |
Fixed and variable rate debt |  |  |  |  |  |  |  |
Principal outstanding |  | $ 300,000,000.0 |  |  |  |  |  |
Interest rate |  | 3.75% |  |  |  |  |  |
Tendered value |  | $ 116,900,000 |  |  |  |  |  |
Tendered percentage |  | 39.00% |  |  |  |  |  |
Tender offer consideration per each $1,000 |  | $ 1,101.92 |  |  |  |  |  |
Make-whole amount |  | $ 24,000,000.0 |  |  |  |  |  |

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