Debt Instrument, Extension Term

No definition available.

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Namespace Prefix:	bdn_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Debt Instrument, Number Of Operating Properties Securing The Debt

+ References

No definition available.

+ Details

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Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Number Of Wholly Owned Subsidiaries Participating In A Loan Agreement

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	instant

- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

+ Details

Name:	us-gaap_DebtInstrumentFaceAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

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+ Details

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Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- 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.

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+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

Name:	us-gaap_DebtInstrumentTerm
Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Weighted average interest rate of debt outstanding.

+ References

No definition available.

+ Details

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Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Aggregate amount of interest expense on all borrowings.

+ References

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+ Details

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Balance Type:	debit
Period Type:	duration

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

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Balance Type:	credit
Period Type:	instant

- Details

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Namespace Prefix:
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Balance Type:
Period Type:

- Details

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- Details

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- Details

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DEBT OBLIGATIONS - Narrative (Details)				3 Months Ended	6 Months Ended
DEBT OBLIGATIONS - Narrative (Details)	Mar. 01, 2023 USD ($)	Jan. 19, 2023 USD ($) subsidiary property	Jun. 30, 2022	Jun. 30, 2023 USD ($)	Jun. 30, 2023 USD ($)
$600 million Unsecured Credit Facility \| Unsecured Debt
Debt Instrument [Line Items]
Maximum borrowing capacity (up to)				$ 600,000,000	$ 600,000,000
Weighted-average interest rate				5.62%	5.62%
Interest expense				$ 400,000
Debt instrument, face amount				600,000,000	$ 600,000,000
$600 million Unsecured Credit Facility \| Unsecured Debt \| Secured Overnight Financing Rate (SOFR) Overnight Index Swap Rate, Before Adjustment
Debt Instrument [Line Items]
Spread on variable rate					1.05%
$600 million Unsecured Credit Facility \| Unsecured Debt \| Daily SOFR Adjustment
Debt Instrument [Line Items]
Spread on variable rate			0.10%		0.10%
Secured Facility \| Secured fixed rate debt
Debt Instrument [Line Items]
Number of wholly owned subsidiaries participating in a loan agreement \| subsidiary		7
Number of operating properties \| property		7
Debt instrument, face amount		$ 245,000,000
Debt instrument, interest rate, stated percentage		5.88%
$70.0 million Term Loan \| Unsecured Debt
Debt Instrument [Line Items]
Debt instrument, face amount	$ 70,000,000.0			$ 70,000,000	$ 70,000,000
Debt instrument, term	1 year
Extension term	12 months
$70.0 million Term Loan \| Unsecured Debt \| Secured Overnight Financing Rate (SOFR) Overnight Index Swap Rate, Before Adjustment
Debt Instrument [Line Items]
Spread on variable rate	1.75%
$70.0 million Term Loan \| Unsecured Debt \| Daily SOFR Adjustment
Debt Instrument [Line Items]
Spread on variable rate	0.10%				0.10%