Deferred Charges, Goodwill And Other Assets, Net (Schedule Of Deferred Charges, Goodwill And Other Assets) (Details) - USD ($) $ in Thousands	9 Months Ended
Sep. 30, 2018	Dec. 31, 2017	Aug. 11, 2017
Deferred Charges, Goodwill And Other Assets [Line Items]
Deferred leasing costs	$ 170,672	$ 199,515
Deferred financing costs - unsecured revolving credit facility	5,328	4,945
Deferred charges, net	176,000	204,460
Accumulated amortization	(67,896)	(98,956)
Deferred charges, net	108,104	105,504
Notes receivable	50,910	50,167
In-place lease values, related intangibles and other assets, net	95,652	102,757
Goodwill	2,945	2,945
Prepaid expenses and other assets, net	83,346	80,947
Total deferred charges, goodwill and other assets, net	$ 340,957	$ 342,320
Notes Receivable 5.85 Interest Rate [Member]
Deferred Charges, Goodwill And Other Assets [Line Items]
Interest rate	5.85%
Notes receivable	$ 44,600		$ 44,700
Loan extension period	3 months
Mortgage loan, maturity date	Jul. 01, 2019
Interest-Free Notes Receivable [Member]
Deferred Charges, Goodwill And Other Assets [Line Items]
Notes receivable	$ 2,300
Mortgage loan, maturity date	Apr. 01, 2023
Disposal Group, Not Discontinued Operations [Member] \| Buyer [Member] \| Notes Receivable 3.0 Interest Rate [Member]
Deferred Charges, Goodwill And Other Assets [Line Items]
Interest rate	3.00%
Notes receivable	$ 4,000
Mortgage loan, maturity date	Oct. 01, 2018

Accumulated Amortization Leasing And Financing Costs

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- Definition

Debt Instrument Extension Period

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Deferred Charges, Goodwill And Other Assets [Line Items]

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Deferred Costs, Gross

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- Definition

Mortgage Loan Maturity Date

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

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Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

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Amount of deferred cost, excluding capitalized cost related to contract with customer; classified as noncurrent.

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- Definition

For an unclassified balance sheet, this element represents costs incurred by the lessor that are (a) costs to originate a lease incurred in transactions with independent third parties that (i) result directly from and are essential to acquire that lease and (ii) would not have been incurred had that leasing transaction not occurred and (b) certain costs directly related to specified activities performed by the lessor for that lease. Those activities are: evaluating the prospective lessee's financial condition; evaluating and recording guarantees, collateral, and other security arrangements; negotiating lease terms; preparing and processing lease documents; and closing the transaction. This amount is before considering accumulated amortization representing the periodic charge to earnings to recognize the deferred costs over the term of the related lease.

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

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- Definition

This element represents the amount of value allocated by a lessor (acquirer) to lease agreements which exist at acquisition of a leased property. Such amount may include the value assigned to existing tenant relationships and excludes the market adjustment component of the value assigned for above or below-market leases acquired.

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Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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- Definition

Amount after allowance and deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements and loans held for sale.

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Amount representing an agreement for an unconditional promise by the maker to pay the entity (holder) a definite sum of money at a future date. Such amount may include accrued interest receivable in accordance with the terms of the note. The note also may contain provisions and related items including a discount or premium, payable on demand, secured, or unsecured, interest bearing or noninterest bearing, among a myriad of other features and characteristics. Excludes amounts related to receivables held-for-sale.

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Amount of assets classified as other.

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Amount of asset related to consideration paid in advance for costs that provide economic benefits in future periods, and amount of other assets.

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