Debt Instrument, Percentage Of Face Amount

No definition available.

Name:	bdn_DebtInstrumentPercentageOfFaceAmount
Namespace Prefix:	bdn_
Data Type:	dtr-types1:percentItemType
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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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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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

Name:	us-gaap_DebtInstrumentLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Fair value amount of debt instrument that was repurchased.

+ References

No definition available.

+ Details

Name:	us-gaap_DebtInstrumentRepurchaseAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Weighted average interest rate of debt outstanding.

+ References

No definition available.

+ Details

Name:	us-gaap_DebtWeightedAverageInterestRate
Namespace Prefix:	us-gaap_
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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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
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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+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The cash inflow from borrowings supported by a written promise to pay an obligation that is uncollateralized (where debt is not backed by the pledge of collateral).

+ References

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Balance Type:	debit
Period Type:	duration

- Details

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Namespace Prefix:
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Balance Type:
Period Type:

- Details

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Period Type:

- Details

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- Details

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DEBT OBLIGATIONS - Narrative (Details) - USD ($)			9 Months Ended
DEBT OBLIGATIONS - Narrative (Details) - USD ($)	Apr. 15, 2024	Apr. 12, 2024	Sep. 30, 2024	Sep. 30, 2023	Jun. 07, 2024
Debt Instrument [Line Items]
Proceeds from unsecured term loan			$ 13,000,000	$ 70,000,000
Unsecured Debt
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage	4.25%
$600.0M Unsecured Credit Facility \| Unsecured Debt
Debt Instrument [Line Items]
Maximum borrowing capacity (up to)			$ 600,000,000
Basis spread on interest rate (as percent)			1.40%
Weighted-average interest rate			6.90%
Interest expense borrowings			$ 1,400,000
Debt instrument, face amount			$ 600,000,000.0
$600.0M Unsecured Credit Facility \| Unsecured Debt \| Daily SOFR Adjustment
Debt Instrument [Line Items]
Basis spread on interest rate (as percent)			0.10%
$350.0M 4.55% Guaranteed Notes due 2029 \| Unsecured Debt
Debt Instrument [Line Items]
Debt instrument, face amount		$ 400,000,000	$ 350,000,000.0
Debt instrument, interest rate, stated percentage		8.875%	4.55%
Percentage of face amount		99.51%
Proceeds from unsecured term loan		$ 391,800,000
$350.0M 4.10% Guaranteed Notes due 2024 \| Unsecured Debt
Debt Instrument [Line Items]
Basis spread on interest rate (as percent)	0.00%
Debt instrument, face amount	$ 335,100,000		$ 350,000,000.0
Debt instrument, interest rate, stated percentage	4.10%		4.10%
Redemption on remaining principal amount					$ 113,400,000