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

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No definition available.

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Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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Contractual interest rate for funds borrowed, under the debt agreement.

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

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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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Including the current and noncurrent portions, aggregate carrying amount of all types of notes payable, as of the balance sheet date, with initial maturities beyond one year or beyond the normal operating cycle, if longer.

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Amount of long-term notes payable classified as other.

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Carrying value as of the balance sheet date, including the current and noncurrent portions, of collateralized debt obligations (with maturities initially due after one year or beyond the operating cycle, if longer). Such obligations include mortgage loans, chattel loans, and any other borrowings secured by assets of the borrower.

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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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Debt (Summary Of Debt Outstanding) (Details) - USD ($) $ in Thousands		12 Months Ended
	Jul. 25, 2019	Dec. 31, 2020	Dec. 15, 2020	Oct. 13, 2020	May 11, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
Mortgages payable		$ 484,111				$ 545,679
Revolving credit facility		0				0
Notes payable		402,776				3,781
Net unamortized discount and debt issuance costs		(494)				(62)
Senior notes and debentures, net		3,404,488				2,807,134
Total debt		4,291,375				3,356,594
Mortgages Payable
Debt Instrument [Line Items]
Principal balance		486,035				547,247
Net unamortized (discount) premium and debt issuance costs		(1,924)				(1,568)
Notes Payable
Debt Instrument [Line Items]
Notes payable		403,270				3,843
Senior Notes and Debentures
Debt Instrument [Line Items]
Principal balance		3,419,200				2,819,200
Net unamortized (discount) premium and debt issuance costs		(14,712)				(12,066)
The Shops at Sunset Place \| Mortgages Payable
Debt Instrument [Line Items]
Principal balance		$ 0				61,987
Interest rate		5.62%
29th Place \| Mortgages Payable
Debt Instrument [Line Items]
Principal balance		$ 0				3,878
Interest rate		5.91%
Sylmar Towne Center \| Mortgages Payable
Debt Instrument [Line Items]
Principal balance		$ 16,236				16,630
Interest rate		5.39%
Plaza Del Sol \| Mortgages Payable
Debt Instrument [Line Items]
Principal balance		$ 8,041				8,230
Interest rate		5.23%
THE AVENUE at White Marsh \| Mortgages Payable
Debt Instrument [Line Items]
Principal balance		$ 52,705				52,705
Interest rate		3.35%
Montrose Crossing \| Mortgages Payable
Debt Instrument [Line Items]
Principal balance		$ 65,596				67,492
Interest rate		4.20%
Azalea \| Mortgages Payable
Debt Instrument [Line Items]
Principal balance		$ 40,000				40,000
Interest rate		3.73%
Bell Gardens \| Mortgages Payable
Debt Instrument [Line Items]
Principal balance		$ 12,408				12,677
Interest rate		4.06%
Plaza El Segundo \| Mortgages Payable
Debt Instrument [Line Items]
Principal balance		$ 125,000				125,000
Interest rate		3.83%
Brook 35 \| Mortgages Payable
Debt Instrument [Line Items]
Principal balance		$ 11,500				11,500
Interest rate		4.65%
Hoboken (24 Buildings) \| Mortgages Payable
Debt Instrument [Line Items]
Principal balance		$ 56,450				56,450
Debt Instrument, Basis Spread on Variable Rate		1.95%
Grove at Shrewsbury (East) \| Mortgages Payable
Debt Instrument [Line Items]
Principal balance		$ 43,600				43,600
Interest rate		3.77%
Hoboken (14 Buildings) \| Mortgages Payable
Debt Instrument [Line Items]
Principal balance		$ 32,705				24,627
Chelsea \| Mortgages Payable
Debt Instrument [Line Items]
Principal balance		$ 5,234				5,597
Interest rate		5.36%
Hoboken (1 Building) \| Mortgages Payable
Debt Instrument [Line Items]
Principal balance		$ 16,560				16,874
Interest rate		3.75%
Term Loan \| Notes Payable
Debt Instrument [Line Items]
Other Notes Payable		$ 400,000				0
Debt Instrument, Basis Spread on Variable Rate		0.90%
Various \| Notes Payable
Debt Instrument [Line Items]
Interest rate		11.31%
Other Notes Payable		$ 3,270				3,843
2.55% notes \| Senior Notes and Debentures
Debt Instrument [Line Items]
Principal balance		$ 0				250,000
Interest rate		2.55%	2.55%
3.00% notes \| Senior Notes and Debentures
Debt Instrument [Line Items]
Principal balance		$ 0				250,000
Interest rate		3.00%
2.75% notes \| Senior Notes and Debentures
Debt Instrument [Line Items]
Principal balance		$ 275,000				275,000
Interest rate		2.75%
3.95% notes \| Senior Notes and Debentures
Debt Instrument [Line Items]
Principal balance		$ 600,000				300,000
Interest rate		3.95%
7.48% debentures \| Senior Notes and Debentures
Debt Instrument [Line Items]
Principal balance		$ 29,200				29,200
Interest rate		7.48%
3.25% Senior notes \| Senior Notes and Debentures
Debt Instrument [Line Items]
Principal balance		$ 475,000				475,000
Interest rate		3.25%
6.82% medium term notes \| Senior Notes and Debentures
Debt Instrument [Line Items]
Principal balance		$ 40,000				40,000
Interest rate		6.82%
3.2% Senior Note \| Senior Notes and Debentures
Debt Instrument [Line Items]
Principal balance		$ 400,000				400,000
Interest rate		3.20%
4.50% notes \| Senior Notes and Debentures
Debt Instrument [Line Items]
Principal balance		$ 550,000				550,000
Interest rate		4.50%
3.625% Senior notes \| Senior Notes and Debentures
Debt Instrument [Line Items]
Principal balance		$ 250,000				250,000
Interest rate		3.625%
1.25% Senior Note [Member] \| Senior Notes and Debentures
Debt Instrument [Line Items]
Principal balance		$ 400,000				0
Interest rate		1.25%		1.25%
3.5% Senior Note [Member] \| Senior Notes and Debentures
Debt Instrument [Line Items]
Principal balance		$ 400,000				$ 0
Interest rate		3.50%			3.50%
Revolving credit facility
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate	0.775%
Revolving credit facility \| Notes Payable
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate		0.775%
Minimum \| Hoboken (14 Buildings) \| Mortgages Payable
Debt Instrument [Line Items]
Interest rate		3.91%
Maximum \| Hoboken (14 Buildings) \| Mortgages Payable
Debt Instrument [Line Items]
Interest rate		5.00%