Accretion of non controlling interest liability.

No definition available.

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- Definition

Business Combination, Future Expected Liability

+ References

No definition available.

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- Definition

Company agreed not to sell acquired properties up to the period

+ References

No definition available.

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- Definition

Leased area of building.

+ References

No definition available.

+ Details

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- Definition

Maximum remaining lease period.

+ References

No definition available.

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- Definition

Minimum remaining lease period.

+ References

No definition available.

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- Definition

Tax guarantee obligation

+ References

No definition available.

+ Details

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- Definition

Amount of liabilities incurred by the acquirer as part of consideration transferred in a business combination.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 30

-Section 25

-Paragraph 5

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 30

-Section 30

-Paragraph 8

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- Definition

The equity interest of noncontrolling shareholders, partners or other equity holders in consolidated entity.

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No definition available.

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- Definition

The amount of the tax credit carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

-Paragraph 3

-Subparagraph (a)

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-Publisher FASB

-Name Accounting Standards Codification

-Glossary Carryforwards

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Commitments and Contingencies (Details) (USD $) In Millions, unless otherwise specified	9 Months Ended	12 Months Ended
	Sep. 30, 2004	Dec. 31, 2014 sqft Y	Dec. 31, 2012
Commitments and Contingencies (Textuals) [Abstract]
Minimum remaining lease period		7bdn_MinimumRemainingLeasePeriod
Maximum remaining lease period		75bdn_MaximumRemainingLeasePeriod
Leased Area Of Building		708,844bdn_LeasedAreaOfBuilding
Amount to be paid if the Company takes fee title to Two Logan Square upon foreclosure of related mortgage		$ 2.9
Liability related to acquisition of TRC	0.7	1.8
Agreed holding period (not to sell) for properties acquired as part of the TRC acquisition		15 years
One Commerce Square [Member]
Commitments and Contingencies (Textuals) [Abstract]
Tax guarantee obligation		125.0
Two Commerce Square [Member]
Commitments and Contingencies (Textuals) [Abstract]
Tax guarantee obligation		100.0
One and Two Commerce Square [Member]
Commitments and Contingencies (Textuals) [Abstract]
Noncontrolling Interest, Ownership Percentage by Noncontrolling Owners		1.00%
Historic Tax Credit Transaction [Member]
Long-term Purchase Commitment [Line Items]
Accretion Of Non Controlling Interest Liability		1.4	1.3
New Markets Tax Credit Transaction [Member]
Commitments and Contingencies (Textuals) [Abstract]
Tax Credit Carryforward, Amount		$ 8.0