Duration interval required to earn subsequent fair value purchase options.

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Land purchase price.

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Lease annual increase percentage.

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lease payment maximum duration period required to adjustment purchase options.

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Lease payment minimum duration period required to adjustment purchase options.

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- Definition

Lease period of aforementioned property benchmarks.

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Maximum duration period required to earn fair value purchase options.

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- Definition

Minimum duration period required to earn fair value purchase options.

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- Definition

Operating partnership units issued.

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Real estate held for sale of geographic location of property.

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Amount equal to the present value (the principal) at the beginning of the lease term of minimum lease payments during the lease term (excluding that portion of the payments representing executory costs such as insurance, maintenance, and taxes to be paid by the lessor, together with any profit thereon) net of payments or other amounts applied to the principal through the balance sheet date.

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Amount due based upon the occurrence of an event specified in the contractual terms.

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The percentage points added to the reference rate to compute the variable rate on the lessee's capital lease.

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No definition available.

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

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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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- Definition

This element represents the amount of gain (loss) on sale of properties during the reporting period net of the applicable income taxes realized.

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- Definition

The charge against earnings in the period to reduce the carrying amount of real property to fair value.

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Date which lease or group of leases is set to expire, in CCYY-MM-DD format.

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No definition available.

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Description of lessee's finance lease.

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The balance represents the amount of loans that are secured by real estate mortgages, offset by the reserve to cover probable credit losses on the loan portfolio.

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- Definition

The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

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- Definition

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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- Definition

Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

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Real Estate (Narrative) (Details) - USD ($)					3 Months Ended		9 Months Ended
Real Estate (Narrative) (Details) - USD ($)	Sep. 28, 2018	Aug. 28, 2018	Aug. 21, 2018	Aug. 08, 2018	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Real Estate Properties [Line Items]
Capital lease obligation					$ 5,398,000		$ 5,398,000
Total revenues					$ 36,170,000	$ 36,398,000	115,088,000	$ 108,871,000
Impairment charges							$ 20,689,000	$ 9,850,000
Land Parcel Adjacent To Riverview Plaza
Real Estate Properties [Line Items]
Purchase price				$ 1,000,000
Cash payments				$ 25,000
Number of OP Units issued				208,000
Senator Square [Member]
Real Estate Properties [Line Items]
Capital lease obligation			$ 5,700,000
Capital Leases obligation interest rate			5.30%
Lease monthly payment			$ 75,000
Lease expiration date			Aug. 31, 2117
Duration required to earn fair value purchase option minimum			25 years
Duration required to earn fair value purchase option maximum			33 years
Duration interval between subsequent fair value purchase option			10 years
Lease terms			The lease initially requires monthly payments of $75,000 through maturity in August 2117 unless the Company exercises one of its options to acquire the land. The first such option will be available between the 25th and 33rd anniversaries of the lease, depending on certain property benchmarks, with additional purchase options every 10 years thereafter during the lease term. The lease also provides for 1.5% annual increases which begin on approximately the 8th anniversary of the lease, depending on the aforementioned property benchmarks.
Lease annual increase percentage			1.50%
Lease period of aforementioned property benchmarks			8 years
Lease payment mnimum duration period required to adjustment purchase options			25 years
Lease payment maximum duration period required to adjustment purchase options			50 years
Interest only mortgage note receivable issued			$ 3,500,000
Interest only mortgage note receivable, interest rate			4.50%
Senator Square [Member] \| Minimum [Member]
Real Estate Properties [Line Items]
Mortgage note receivable maturity date			26 years 6 months
Senator Square [Member] \| Maximum [Member]
Real Estate Properties [Line Items]
Mortgage note receivable maturity date			34 years 6 months
Mechanicsburg Center [Member]
Real Estate Properties [Line Items]
Gain on sale of real estate		$ 4,900,000
Mechanicsburg Center [Member] \| Real Estate [Member]
Real Estate Properties [Line Items]
Total revenues		$ 16,100,000
West Bridgewater Plaza [Member]
Real Estate Properties [Line Items]
Impairment charges	$ 9,400,000
West Bridgewater Plaza [Member] \| Real Estate [Member]
Real Estate Properties [Line Items]
Total revenues	$ 3,500,000
Carll's Corner [Member]
Real Estate Properties [Line Items]
Location							Bridgeton, New Jersey
Maxatawny Marketplace [Member]
Real Estate Properties [Line Items]
Location							Maxatawny, Pennsylvania
Real Estate Held for Sale [Member]
Real Estate Properties [Line Items]
Impairment charges							$ 11,300,000