Earnings per common partnership unit line items.

No definition available.

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- Definition

Repurchase program number of mirror unit of operating partnership retired for each common share repurchased.

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Aggregate dividends declared during the period for each share of common stock outstanding.

+ References

+ Details

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Period Type:	duration

- Definition

Amount of paid and unpaid common stock dividends declared with the form of settlement in cash, stock and payment-in-kind (PIK).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480008/505-10-S99-1

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 45
-Paragraph 2
-SubTopic 405
-Topic 942
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477787/942-405-45-2

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Number of shares that have been repurchased and retired during the period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-SubTopic 10
-Topic 505
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481112/505-10-50-2

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(28))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(29))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480008/505-10-S99-1

+ Details

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- Details

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- Details

Name:	dei_LegalEntityAxis=bdn_BrandywineOperatingPartnershipL.P.Member
Namespace Prefix:
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PARTNERS' EQUITY OF THE PARENT COMPANY - Narrative (Details) - USD ($) $ / shares in Units, $ in Millions		3 Months Ended				6 Months Ended
	Jul. 17, 2025	Jun. 30, 2025	Mar. 31, 2025	Jun. 30, 2024	Mar. 31, 2024	Jun. 30, 2025	Jun. 30, 2024
Earnings Per Common Partnership Unit [Line Items]
Distributions declared (in dollars per share)		$ 0.15	$ 0.15	$ 0.15	$ 0.15
Repurchased and retired (in shares)						0	0
Subsequent Event
Earnings Per Common Partnership Unit [Line Items]
Amount of dividend declared	$ 26.5
Brandywine Operating Partnership, L.P.
Earnings Per Common Partnership Unit [Line Items]
Distributions declared (in dollars per share)		$ 0.15
Repurchase program, ratio of mirror unit of operating partnership retired for each common share repurchased						1
Brandywine Operating Partnership, L.P. \| Subsequent Event
Earnings Per Common Partnership Unit [Line Items]
Amount of dividend declared	$ 26.5