Acquisition costs capitalized in asset acquisition.

No definition available.

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Namespace Prefix:	bdn_
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- Definition

Contractual sale price of real estate acquired.

+ References

No definition available.

+ Details

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Balance Type:	debit
Period Type:	instant

- Definition

Area of a real estate property.

+ References

No definition available.

+ Details

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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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- Definition

The cash outflow for acquisition of buildings (properties) whether for investment or use.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 13
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3213-108585

+ Details

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Period Type:	duration

- Definition

The aggregate revenue from real estate operations during the reporting period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.1(e))
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

+ Details

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Balance Type:	credit
Period Type:	duration

- Details

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- Details

Name:	us-gaap_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis=us-gaap_OfficeBuildingMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Real Estate Investments - Acquisitions (Textual) (Details) $ in Thousands		2 Months Ended	3 Months Ended		9 Months Ended
	Jul. 28, 2017 USD ($) ft²	Sep. 30, 2017 USD ($)	Sep. 30, 2017 USD ($)	Sep. 30, 2016 USD ($)	Sep. 30, 2017 USD ($)	Sep. 30, 2016 USD ($)
Business Acquisition [Line Items]
Revenue			$ 128,438	$ 129,694	$ 387,149	$ 393,377
3000 Market Street [Member]
Business Acquisition [Line Items]
Acquisition of office building from unaffiliated third party, cost	$ 32,700
Capitalized acquisition related cost	700
Contractual sale price of real estate acquired	$ 32,000
Revenue		$ 300
3000 Market Street [Member] \| Office Properties [Member]
Business Acquisition [Line Items]
Area of Real Estate Property \| ft²	58,587