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Not to exceed amount.

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

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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.

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

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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.

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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.

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

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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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Commitments and Contingencies (Textual) (Details) - USD ($) $ in Millions		6 Months Ended
	Apr. 02, 2015	Jun. 30, 2016	Dec. 03, 2015
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		140.1
Capital Expenditures For Tenant Improvements [Member]
Property Subject to or Available for Operating Lease [Line Items]
Contractual obligations		57.8
Subaru of America [Member]
Property Subject to or Available for Operating Lease [Line Items]
NTE Amount			$ 77.3
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
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