Area of a real estate property.

No definition available.

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- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)(1)
-URI https://asc.fasb.org/extlink&oid=114001798&loc=d3e33918-111571

+ Details

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- Definition

The book value of investments in real estate joint ventures including direct and indirect investments.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03.1(d))
-URI https://asc.fasb.org/extlink&oid=126734703&loc=d3e572229-122910

+ Details

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Period Type:	instant

- Definition

Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

+ References

No definition available.

+ Details

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- Details

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- Details

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- Details

Name:	dei_LegalEntityAxis=bdn_JointVentureWithUnaffiliatedThirdPartyMember
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- Details

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SUBSEQUENT EVENTS (Details) $ in Thousands	Jul. 14, 2022 USD ($) ft²	Jun. 30, 2022 USD ($) ft²	Dec. 31, 2021 USD ($)
Subsequent Event [Line Items]
Rentable area (in square feet) \| ft²		13,639,287
Investment in real estate ventures		$ 429,246	$ 411,110
Subsequent Event \| 3151 Market Street
Subsequent Event [Line Items]
Rentable area (in square feet) \| ft²	417,000
Investment in real estate ventures	$ 307,000
Subsequent Event \| 3151 Market Street \| Joint Venture With Unaffiliated Third Party
Subsequent Event [Line Items]
Investment in real estate ventures	$ 55,000
Subsequent Event \| 3151 Market Street \| Joint Venture With Unaffiliated Third Party \| Joint Venture With Unaffiliated Third Party
Subsequent Event [Line Items]
Equity method investment, ownership percentage	45.00%