Number of Communities Encumbered.

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Secured debt including debt on real estate held for sale.

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No definition available.

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Unsecured short-term debt instrument issued by corporations which are highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify under that definition. Original maturity means original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three-years ago does not become a cash equivalent when its remaining maturity is three months.

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The average effective interest rate during the reporting period.

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Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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No definition available.

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Amount, after accumulated amortization, of debt discount.

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Amount of unamortized debt discount (premium) and debt issuance costs.

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Amount, after accumulated amortization, of debt premium.

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Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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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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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Including the current and noncurrent portions, carrying value as of the balance sheet date of Notes with the highest claim on the assets of the issuer in case of bankruptcy or liquidation (with maturities initially due after one year or beyond the operating cycle if longer). Senior note holders are paid off in full before any payments are made to junior note holders.

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Including the current and noncurrent portions, carrying value as of the balance sheet date of uncollateralized debt obligations (with maturities initially due after one year or beyond the operating cycle if longer).

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SECURED AND UNSECURED DEBT, NET - Summary (Details) $ in Thousands	6 Months Ended
	Jun. 30, 2020 USD ($) community	Feb. 29, 2020 USD ($)	Dec. 31, 2019 USD ($)
Secured debt instruments
Unamortized net premium	$ 30,200		$ 35,300
Interest rate at end of the period	3.24%
Long-term Debt	$ 4,766,804		4,707,524
Unsecured Debt	3,653,934		3,558,083
Borrowings outstanding	$ 2,900		2,900
Weighted Average
Secured debt instruments
Years to maturity	7 years
Commercial Paper
Secured debt instruments
Borrowings outstanding at end of period	$ 185,000		300,000
Mortgages Note Payable \| Fixed Rate Debt
Secured debt instruments
Principal outstanding	$ 855,585		884,869
Interest rate at end of the period	3.60%
Number of Communities Encumbered \| community	14
Mortgages Note Payable \| Fixed Rate Debt \| Weighted Average
Secured debt instruments
Years to maturity	5 years 10 months 24 days
Tax-exempt secured notes payable \| Variable Rate Debt
Secured debt instruments
Principal outstanding	$ 27,000		27,000
Interest rate at end of the period	0.85%
Number of Communities Encumbered \| community	1
Tax-exempt secured notes payable \| Variable Rate Debt \| Weighted Average
Secured debt instruments
Years to maturity	11 years 8 months 12 days
Credit facilities \| Fixed Rate Debt
Secured debt instruments
Principal outstanding	$ 202,254		204,590
Interest rate at end of the period	4.90%
Number of Communities Encumbered \| community	4
Credit facilities \| Fixed Rate Debt \| Weighted Average
Secured debt instruments
Years to maturity	2 years 6 months
Secured Debt
Secured debt instruments
Principal outstanding	$ 1,112,870		1,149,441
Interest rate at end of the period	3.77%
Long-term Debt	$ 1,112,870
Number of Communities Encumbered \| community	19
Secured Debt \| Weighted Average
Secured debt instruments
Years to maturity	5 years 4 months 24 days
Secured Debt \| Fixed Rate Debt
Secured debt instruments
Principal outstanding	$ 1,085,941		1,122,505
Interest rate at end of the period	3.85%
Long-term Debt	$ 1,085,941
Number of Communities Encumbered \| community	18
Deferred financing costs and other non-cash adjustments	$ (28,102)		(33,046)
Secured Debt \| Fixed Rate Debt \| Weighted Average
Secured debt instruments
Years to maturity	5 years 2 months 12 days
Secured Debt \| Variable Rate Debt
Secured debt instruments
Principal outstanding	$ 26,929		26,936
Interest rate at end of the period	0.85%
Long-term Debt	$ 26,929
Number of Communities Encumbered \| community	1
Deferred finance costs, net	$ (71)		(64)
Secured Debt \| Variable Rate Debt \| Weighted Average
Secured debt instruments
Years to maturity	11 years 8 months 12 days
Unsecured Revolving credit facility due 2023 \| Weighted Average
Secured debt instruments
Years to maturity	2 years 7 months 6 days
Unsecured Revolving credit facility due 2020 \| Commercial Paper
Secured debt instruments
Interest rate at end of the period	0.45%
Borrowings outstanding at end of period	$ 185,000		300,000
Unsecured Revolving credit facility due 2020 \| Commercial Paper \| Weighted Average
Secured debt instruments
Years to maturity	1 month 6 days
Unsecured Working Capital Credit Facility
Secured debt instruments
Interest rate at end of the period	0.99%
Borrowings outstanding	$ 17,180		16,583
Unsecured Working Capital Credit Facility \| Weighted Average
Secured debt instruments
Years to maturity	6 months
Term Loan due September 2023
Secured debt instruments
Interest rate at end of the period	1.07%
Senior Notes	$ 35,000		35,000
Term Loan due September 2023 \| Weighted Average
Secured debt instruments
Years to maturity	3 years 3 months 18 days
1.93% Term Loan due September 2023
Secured debt instruments
Interest rate at end of the period	1.93%
Senior Notes	$ 315,000		315,000
1.93% Term Loan due September 2023 \| Weighted Average
Secured debt instruments
Years to maturity	3 years 3 months 18 days
3.75% Medium-Term Notes Due July 2024
Secured debt instruments
Unamortized discount	$ 417		470
Interest rate at end of the period	3.75%
Senior Notes	$ 299,583		299,530
3.75% Medium-Term Notes Due July 2024 \| Weighted Average
Secured debt instruments
Years to maturity	4 years
8.50% Debentures, Due September 2024
Secured debt instruments
Interest rate at end of the period	8.50%
Senior Notes	$ 15,644		15,644
8.50% Debentures, Due September 2024 \| Weighted Average
Secured debt instruments
Years to maturity	4 years 2 months 12 days
4.00% Medium-Term Note due October 2025
Secured debt instruments
Unamortized discount	$ 362		396
Interest rate at end of the period	4.00%
Senior Notes	$ 299,638		299,604
4.00% Medium-Term Note due October 2025 \| Weighted Average
Secured debt instruments
Years to maturity	5 years 3 months 18 days
2.95% Medium-Term Note due September 2026
Secured debt instruments
Interest rate at end of the period	2.95%
Senior Notes	$ 300,000		300,000
2.95% Medium-Term Note due September 2026 \| Weighted Average
Secured debt instruments
Years to maturity	6 years 2 months 12 days
3.50 Medium-Term Note due July 2027
Secured debt instruments
Unamortized discount	$ 494		529
Interest rate at end of the period	3.50%
Senior Notes	$ 299,506		299,471
3.50 Medium-Term Note due July 2027 \| Weighted Average
Secured debt instruments
Years to maturity	7 years
3.50% Medium-Term Notes Due January 2028
Secured debt instruments
Unamortized discount	$ 894		954
Interest rate at end of the period	3.50%
Senior Notes	$ 299,106		299,046
3.50% Medium-Term Notes Due January 2028 \| Weighted Average
Secured debt instruments
Years to maturity	7 years 6 months
4.40% Medium-Term Notes due January 2029
Secured debt instruments
Unamortized discount	$ 5		5
Interest rate at end of the period	4.40%
Senior Notes	$ 299,995		299,995
4.40% Medium-Term Notes due January 2029 \| Weighted Average
Secured debt instruments
Years to maturity	8 years 7 months 6 days
3.20% Medium-Term Notes due January 2030
Secured debt instruments
Unamortized discount	$ 13,099		2,281
Interest rate at end of the period	3.20%
Senior Notes	$ 613,099	$ 600,000	402,281
3.20% Medium-Term Notes due January 2030 \| Weighted Average
Secured debt instruments
Years to maturity	9 years 6 months
3.00% Medium-Term Notes due August 2031
Secured debt instruments
Unamortized discount	$ 1,075		1,123
Interest rate at end of the period	3.00%
Senior Notes	$ 398,925		398,877
3.00% Medium-Term Notes due August 2031 \| Weighted Average
Secured debt instruments
Years to maturity	11 years 1 month 6 days
3.10% Medium-Term Notes due November 2034
Secured debt instruments
Principal outstanding	$ 298,735
Unamortized discount	$ 1,265		1,309
Interest rate at end of the period	3.10%
Senior Notes			298,691
3.10% Medium-Term Notes due November 2034 \| Weighted Average
Secured debt instruments
Years to maturity	14 years 3 months 18 days
Other
Secured debt instruments
Senior Notes	$ 12		13
Unsecured Debt
Secured debt instruments
Interest rate at end of the period	3.26%
Long-term Debt	$ 3,653,934
Unsecured Debt	3,653,934		3,558,083
Deferred finance costs, net	$ (22,489)		(21,652)
Unsecured Debt \| Weighted Average
Secured debt instruments
Years to maturity	7 years 4 months 24 days
Credit facilities
Secured debt instruments
Principal outstanding	$ 202,300
Credit facilities \| Fixed Rate Debt
Secured debt instruments
Interest rate at end of the period	4.90%
United Dominion Realty L.P.
Secured debt instruments
Interest rate at end of the period	2.54%
Long-term Debt	$ 99,082		99,071
Number of Communities Encumbered \| community	2
United Dominion Realty L.P. \| Weighted Average
Secured debt instruments
Years to maturity	10 years 2 months 12 days
United Dominion Realty L.P. \| Fixed Rate Debt
Secured debt instruments
Interest rate at end of the period	3.10%
Long-term Debt	$ 72,153		72,135
Number of Communities Encumbered \| community	1
United Dominion Realty L.P. \| Fixed Rate Debt \| Weighted Average
Secured debt instruments
Years to maturity	9 years 7 months 6 days
United Dominion Realty L.P. \| Variable Rate Debt
Secured debt instruments
Interest rate at end of the period	0.85%
Long-term Debt	$ 26,929		26,936
Number of Communities Encumbered \| community	1
Deferred finance costs, net	$ (71)		(64)
United Dominion Realty L.P. \| Variable Rate Debt \| Weighted Average
Secured debt instruments
Years to maturity	11 years 8 months 12 days
United Dominion Realty L.P. \| Mortgages Note Payable
Secured debt instruments
Principal outstanding	$ 72,500
United Dominion Realty L.P. \| Mortgages Note Payable \| Fixed Rate Debt
Secured debt instruments
Principal outstanding	$ 72,500		72,500
Interest rate at end of the period	3.10%
Number of Communities Encumbered \| community	1
Deferred finance costs, net	$ (347)		(365)
United Dominion Realty L.P. \| Mortgages Note Payable \| Fixed Rate Debt \| Weighted Average
Secured debt instruments
Years to maturity	9 years 7 months 6 days
United Dominion Realty L.P. \| Tax-exempt secured notes payable \| Variable Rate Debt
Secured debt instruments
Principal outstanding	$ 27,000		$ 27,000
Interest rate at end of the period	0.85%
Number of Communities Encumbered \| community	1
United Dominion Realty L.P. \| Tax-exempt secured notes payable \| Variable Rate Debt \| Weighted Average
Secured debt instruments
Years to maturity	11 years 8 months 12 days