Equity Method Investment Summarized Financial Information Debt.

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- Definition

Loss on real estate venture formation

+ References

No definition available.

+ Details

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- Definition

Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 470

-SubTopic 10

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6802200&loc=d3e1835-112601

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 235

-SubTopic 10

-Section S99

-Paragraph 3

-Subparagraph (SX 210.12-04.(a))

-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e24072-122690

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- Definition

Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

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- Definition

Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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- Definition

Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

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- Definition

Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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- Definition

Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

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Investment in Unconsolidated Ventures Aggregate Principal Payments of Recourse and Non-recourse Debt Payable to Third-parties (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Jul. 31, 2014
Equity Method Investments and Joint Ventures [Abstract]
Loss on real estate venture formation	$ 0bdn_LossOnRealEstateVentureFormation	$ 0bdn_LossOnRealEstateVentureFormation	$ (950)bdn_LossOnRealEstateVentureFormation
Schedule of Equity Method Investments [Line Items]
2015	102,030
2016	367,703
2017	330,323
2018	336,954
2019	213,155
Thereafter	1,109,298
Equity Method Investment Summarized Financial Information Debt	965,077
Brandywine Nineteen Nineteen Ventures [Member]
Schedule of Equity Method Investments [Line Items]
Equity Method Investment Summarized Financial Information Debt	0
Austin Joint Venture [Member]
Schedule of Equity Method Investments [Line Items]
Equity Method Investment Summarized Financial Information Debt	382,100			34,500
Equity Method Investments [Member]
Schedule of Equity Method Investments [Line Items]
2015	279,351
2016	133,809
2017	44,465
2018	231,030
2019	182,522
Thereafter	93,900
Equity Method Investment Summarized Financial Information Debt	965,077
Seven Tower Bridge [Member]
Schedule of Equity Method Investments [Line Items]
Equity Method Investment Summarized Financial Information Debt	14,865
Fixed Rate Loan Maturing February 2016 [Member] \| Secured Debt [Member] \| Seven Tower Bridge [Member]
Schedule of Equity Method Investments [Line Items]
Equity Method Investment Summarized Financial Information Debt	2,000
Fixed Rate Loan Maturing March 2020 [Member] \| Secured Debt [Member] \| Seven Tower Bridge [Member]
Schedule of Equity Method Investments [Line Items]
Equity Method Investment Summarized Financial Information Debt	$ 3,900