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

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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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Number of stories in a high-rise building

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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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- Definition

The amount of loss pertaining to the specified contingency that was charged against earnings in the period, including the effects of revisions in previously reported estimates.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=82911808&loc=d3e14326-108349

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- Definition

Net rentable area for properties owned.

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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.

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Liberty Property 18th & Arch LP and Liberty Property 18th & Arch, Hotel, LP (Details) $ in Thousands	3 Months Ended
	Jun. 30, 2018 USD ($) ft²	Dec. 31, 2017 USD ($)	Jun. 30, 2014 ft² room story investment
Schedule of Equity Method Investments [Line Items]
Investments in and advances to unconsolidated joint ventures	$ 359,776	$ 288,456
Liberty Property 18th & Arch [Member]
Schedule of Equity Method Investments [Line Items]
Investments in and advances to unconsolidated joint ventures	188,200
Philadelphia [Member] \| Liberty Property 18th & Arch [Member]
Schedule of Equity Method Investments [Line Items]
Number of equity method investments \| investment			2
Anticipated Aggregate Investment	960,000
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	$ 222,600
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
GMP Contract for 18th & Arch [Member] \| Threatened Litigation [Member] \| Other Liabilities [Member] \| Development Service Fee Expense [Member] \| Philadelphia [Member] \| Liberty Property 18th & Arch [Member] \| Guarantee Obligations [Member]
Loss Contingency [Abstract]
Loss Contingency, Loss in Period	$ 60,000