Debt Instrument, Extension Term

No definition available.

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

- Definition

Debt Instrument, Number Of Extensions

+ References

No definition available.

+ Details

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

- Definition

Line Of Credit Facility, Funds From Operations, Payout Ratio

+ References

No definition available.

+ Details

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

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

- 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.

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+ Details

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

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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Period Type:

DEBT OBLIGATIONS - Narrative (Details) - Unsecured term loans, net		6 Months Ended
	May 28, 2026 extension	Jun. 30, 2026 USD ($)	Sep. 26, 2025
Debt Covenant Period 1
Debt Instrument [Line Items]
Payout ratio			100.00%
Debt Covenant Period 2
Debt Instrument [Line Items]
Payout ratio			95.00%
$600.0M Unsecured Credit Facility
Debt Instrument [Line Items]
Maximum borrowing capacity (up to)		$ 600,000,000.0
Weighted-average interest rate		5.15%
Interest expense borrowings		$ 1,900,000
Extension term	6 months
Number of extensions \| extension	1
$600.0M Unsecured Credit Facility \| Daily Simple SOFR
Debt Instrument [Line Items]
Basis spread on interest rate		1.40%
$600.0M Unsecured Credit Facility \| Daily SOFR Adjustment
Debt Instrument [Line Items]
Basis spread on interest rate		0.10%