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No definition available.

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- Definition

Exercise price of put option, where an unaffiliated third party has unilateral option to exercise.

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- Definition

Amount of liability recognized arising from contingent consideration in a business combination.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
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- Definition

Fair value at acquisition-date of the equity interest in the acquiree held by the acquirer, immediately before the acquisition date for businesses combined in stages.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Amount of contractual obligation, including but not limited to, long-term debt, capital lease obligations, operating lease obligations, purchase obligations, and other commitments.

+ References

No definition available.

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- Definition

This item represents a non-contingent liability for the fair value of an obligation to stand ready to perform over the term of a guaranty issued in the event that specified triggering events or conditions occur.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
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-Section 25
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- Definition

Term of the lessee's leasing arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

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- Definition

The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

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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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Commitments and Contingencies (Textual) (Details) - USD ($) $ in Millions		3 Months Ended
	Apr. 02, 2015	Mar. 31, 2016
Property Subject to or Available for Operating Lease [Line Items]
Associated letter of credit		$ 10.0
Development And Redevelopment [Member]
Property Subject to or Available for Operating Lease [Line Items]
Contractual obligations		196.4
Capital Expenditures For Tenant Improvements [Member]
Property Subject to or Available for Operating Lease [Line Items]
Contractual obligations		54.0
TB-BDN Plymouth Apartments [Member]
Property Subject to or Available for Operating Lease [Line Items]
Guarantor obligations, current carrying value		3.2
Construction Loan		56.0
1919 Venture [Member]
Property Subject to or Available for Operating Lease [Line Items]
Guarantor obligations, current carrying value		88.9
evo at Cira Centre South Venture [Member]
Property Subject to or Available for Operating Lease [Line Items]
Guarantor obligations, current carrying value		26.5
Construction Loan		97.8
PJP VII [Member]
Property Subject to or Available for Operating Lease [Line Items]
Guarantor obligations, current carrying value		0.5
A618 Market Street
Property Subject to or Available for Operating Lease [Line Items]
Contingent consideration, liability	$ 2.0	1.7
Fair value of contingent consideration	$ 1.6
Put Option [Member]
Property Subject to or Available for Operating Lease [Line Items]
Purchase price		$ 35.0
Minimum [Member]
Property Subject to or Available for Operating Lease [Line Items]
Lease terms		5 years
Maximum [Member]
Property Subject to or Available for Operating Lease [Line Items]
Lease terms		73 years