Total anticipated cost of investment in assets including but not limited to assets under construction.

No definition available.

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- Definition

Anticipated balance in investment in unconsolidated joint ventures after development is completed.

+ References

No definition available.

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- Definition

Number of equity method investments

+ References

No definition available.

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- Definition

Number of hotel rooms in a hotel

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No definition available.

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- Definition

Number of stories in a high-rise building

+ References

No definition available.

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- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=66011266&loc=d3e33918-111571

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- Definition

Total investments in (A) an entity in which the entity has significant influence, but does not have control, (B) subsidiaries that are not required to be consolidated and are accounted for using the equity and or cost method, and (C) an entity in which the reporting entity shares control of the entity with another party or group. Includes long-term advances receivable from a party that is affiliated with the reporting entity by means of direct or indirect ownership.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.12)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- References

No definition available.

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- Definition

Reflects the estimated amount of loss from the specified contingency as of the balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=82911808&loc=d3e14435-108349

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 9
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=82911808&loc=d3e14557-108349

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- Definition

Net rentable area for properties owned.

+ References

No definition available.

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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.

+ References

No definition available.

+ Details

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Liberty Property 18th & Arch LP and Liberty Property 18th & Arch, Hotel, LP (Details) $ in Thousands	Mar. 31, 2018 USD ($) ft²	Dec. 31, 2017 USD ($)	Jun. 30, 2014 ft² room investment story
Schedule of Equity Method Investments [Line Items]
Investments in and advances to unconsolidated joint ventures	$ 350,458	$ 288,456
Liberty Property 18th & Arch [Member]
Schedule of Equity Method Investments [Line Items]
Investments in and advances to unconsolidated joint ventures	179,200
Philadelphia [Member] \| Liberty Property 18th & Arch [Member]
Schedule of Equity Method Investments [Line Items]
Number of equity method investments \| investment			2
Anticipated Aggregate Investment	955,300
Anticipated investment in joint ventures	$ 191,100
Ownership percentage of equity method investment	20.00%
Philadelphia [Member] \| Liberty Property 18th & Arch [Member] \| Guarantee Obligations [Member]
Loss Contingency [Abstract]
Possible cost overruns	$ 67,000
Philadelphia [Member] \| Construction in Progress [Member] \| Liberty Property 18th & Arch [Member]
Schedule of Equity Method Investments [Line Items]
Number of stories in a high-rise building \| story			60
Leaseable square feet \| ft²			1,300,000
Number of hotel rooms \| room			217
Anticipated Aggregate Investment	$ 217,400
Philadelphia [Member] \| Building and Building Improvements [Member] \| Liberty Property 18th & Arch [Member]
Schedule of Equity Method Investments [Line Items]
Leaseable square feet \| ft²	250,000
Anticipated Aggregate Investment	$ 138,300