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Real Estate Investments, Acquisitions and Dispositions (Details) (USD $) | 3 Months Ended | 12 Months Ended | 0 Months Ended |  |  |  |  |  |  |
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Dec. 31, 2014 acre | Sep. 30, 2014 | Jun. 30, 2014 | Mar. 31, 2014 | Dec. 31, 2013 | Sep. 30, 2013 | Jun. 30, 2013 | Mar. 31, 2013 | Dec. 31, 2014 acre | Dec. 31, 2013 | Dec. 31, 2012 | Dec. 19, 2013 sqft Storey | Oct. 17, 2013 sqft | Jun. 14, 2013 sqft | Apr. 07, 2014 | Jul. 18, 2012 sqft | Jun. 22, 2012 sqft | Mar. 22, 2012 sqft | Jan. 17, 2012 sqft | Jun. 28, 2013 sqft | Jun. 19, 2013 sqft | Feb. 19, 2014 Properties Storey sqft acre | Apr. 25, 2013 acre | Apr. 03, 2014 | Oct. 16, 2013 | Nov. 19, 2013 acre | Mar. 27, 2014 acre | Apr. 16, 2014 acre | Aug. 05, 2013 acre | Feb. 25, 2013 sqft Properties | Oct. 17, 2014 sqft Real_Estate_Investments | Jul. 31, 2014 Properties
Significant Acquisitions and Disposals [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Provision for impairment on assets held for sale |  |  |  |  |  |  |  |  | $ 1,765,000 us-gaap_ImpairmentOfLongLivedAssetsToBeDisposedOf | $ 0 us-gaap_ImpairmentOfLongLivedAssetsToBeDisposedOf | $ 0 us-gaap_ImpairmentOfLongLivedAssetsToBeDisposedOf |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Business Acquisition, Pro Forma Revenue |  |  |  |  |  |  |  |  |  | 610,979,000 us-gaap_BusinessAcquisitionsProFormaRevenue | 592,753,000 us-gaap_BusinessAcquisitionsProFormaRevenue |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Business Combination, Pro Forma Information, Revenue of Acquiree since Acquisition Date, Actual |  |  |  |  |  |  |  |  |  | 3,400,000 us-gaap_BusinessCombinationProFormaInformationRevenueOfAcquireeSinceAcquisitionDateActual |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Business Combination, Pro Forma Information, Earnings or Loss of Acquiree since Acquisition Date, Actual |  |  |  |  |  |  |  |  |  | 200,000 us-gaap_BusinessCombinationProFormaInformationEarningsOrLossOfAcquireeSinceAcquisitionDateActual |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Net gain (loss) on sale of undepreciated real estate |  |  |  |  |  |  |  |  | 458,000 us-gaap_BusinessCombinationStepAcquisitionEquityInterestInAcquireeRemeasurementGain | 6,866,000 us-gaap_BusinessCombinationStepAcquisitionEquityInterestInAcquireeRemeasurementGain | 0 us-gaap_BusinessCombinationStepAcquisitionEquityInterestInAcquireeRemeasurementGain |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Land | 669,635,000 us-gaap_Land |  |  |  | 680,513,000 us-gaap_Land |  |  |  | 669,635,000 us-gaap_Land | 680,513,000 us-gaap_Land |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Adjustment to Record Land Acquisition to Fair Value |  |  |  |  |  |  |  |  | 0 bdn_AdjustmenttoRecordLandAcquisitiontoFairValue | 7,752,000 bdn_AdjustmenttoRecordLandAcquisitiontoFairValue | 0 bdn_AdjustmenttoRecordLandAcquisitiontoFairValue |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Payments to Acquire Real Estate |  |  |  |  |  |  |  |  | 18,443,000 us-gaap_PaymentsToAcquireRealEstate | 161,604,000 us-gaap_PaymentsToAcquireRealEstate | 77,555,000 us-gaap_PaymentsToAcquireRealEstate |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Gains (Losses) on Sales of Investment Real Estate |  |  |  |  |  |  |  |  | 4,901,000 us-gaap_GainsLossesOnSalesOfInvestmentRealEstate | 0 us-gaap_GainsLossesOnSalesOfInvestmentRealEstate | 0 us-gaap_GainsLossesOnSalesOfInvestmentRealEstate |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Equity Method Investments | 225,004,000 us-gaap_EquityMethodInvestments |  |  |  | 180,512,000 us-gaap_EquityMethodInvestments |  |  |  | 225,004,000 us-gaap_EquityMethodInvestments | 180,512,000 us-gaap_EquityMethodInvestments | 193,555,000 us-gaap_EquityMethodInvestments |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Secured Debt | 654,590,000 us-gaap_SecuredDebt |  |  |  | 670,151,000 us-gaap_SecuredDebt |  |  |  | 654,590,000 us-gaap_SecuredDebt | 670,151,000 us-gaap_SecuredDebt |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Balance of the Financing Obligation | 37,558,000 us-gaap_OtherLiabilities |  |  |  | 32,923,000 us-gaap_OtherLiabilities |  |  |  | 37,558,000 us-gaap_OtherLiabilities | 32,923,000 us-gaap_OtherLiabilities |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Gain (Loss) on Sale of Properties |  |  |  |  |  |  |  |  | 900,000 us-gaap_DiscontinuedOperationGainLossOnDisposalOfDiscontinuedOperationNetOfTax | 3,382,000 us-gaap_DiscontinuedOperationGainLossOnDisposalOfDiscontinuedOperationNetOfTax | 34,774,000 us-gaap_DiscontinuedOperationGainLossOnDisposalOfDiscontinuedOperationNetOfTax |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Net gain (loss) on sale of undepreciated real estate |  |  |  |  |  |  |  |  | 1,184,000 bdn_Netgainlossonsaleofundepreciatedrealestate | (137,000)bdn_Netgainlossonsaleofundepreciatedrealestate | 0 bdn_Netgainlossonsaleofundepreciatedrealestate |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Area Owned By Real Estate Venture Of Undeveloped Parcels Of Land | 3.0 bdn_AreaOwnedByRealEstateVentureOfUndevelopedParcelsOfLand |  |  |  |  |  |  |  | 3.0 bdn_AreaOwnedByRealEstateVentureOfUndevelopedParcelsOfLand |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Business Acquisition, Pro Forma Income (Loss) from Continuing Operations before Changes in Accounting and Extraordinary Items, Net of Tax |  |  |  |  |  |  |  |  |  | 21,805,000 us-gaap_BusinessAcquisitionsProFormaIncomeLossFromContinuingOperationsBeforeChangesInAccountingAndExtraordinaryItemsNetOfTax | (60,011,000)us-gaap_BusinessAcquisitionsProFormaIncomeLossFromContinuingOperationsBeforeChangesInAccountingAndExtraordinaryItemsNetOfTax |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Business Acquisition, Pro Forma Net Income (Loss) |  |  |  |  |  |  |  |  |  | 25,957,000 us-gaap_BusinessAcquisitionsProFormaNetIncomeLoss | (16,970,000)us-gaap_BusinessAcquisitionsProFormaNetIncomeLoss |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Continuing operations (in dollars per share) |  |  |  |  |  |  |  |  | $ (0.01)us-gaap_IncomeLossFromContinuingOperationsPerBasicShare | $ 0.20 us-gaap_IncomeLossFromContinuingOperationsPerBasicShare | $ (0.36)us-gaap_IncomeLossFromContinuingOperationsPerBasicShare |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Business Acquisition, Pro Forma Income (Loss) from Continuing Operations before Changes in Accounting and Extraordinary Items, Net of Tax, Per Share, Basic |  |  |  |  |  |  |  |  |  | $ 0.14 us-gaap_BusinessAcquisitionProFormaIncomeLossFromContinuingOperationsBeforeChangesInAccountingAndExtraordinaryItemsNetOfTaxPerShareBasic | $ (0.42)us-gaap_BusinessAcquisitionProFormaIncomeLossFromContinuingOperationsBeforeChangesInAccountingAndExtraordinaryItemsNetOfTaxPerShareBasic |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Income (Loss) from Continuing Operations, Per Diluted Share |  |  |  |  |  |  |  |  | $ (0.01)us-gaap_IncomeLossFromContinuingOperationsPerDilutedShare | $ 0.20 us-gaap_IncomeLossFromContinuingOperationsPerDilutedShare | $ (0.36)us-gaap_IncomeLossFromContinuingOperationsPerDilutedShare |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Business Acquisition, Pro Forma Income (Loss) from Continuing Operations before Changes in Accounting and Extraordinary Items, Net of Tax, Per Share, Diluted |  |  |  |  |  |  |  |  |  | $ 0.14 us-gaap_BusinessAcquisitionProFormaIncomeLossFromContinuingOperationsBeforeChangesInAccountingAndExtraordinaryItemsNetOfTaxPerShareDiluted | $ (0.42)us-gaap_BusinessAcquisitionProFormaIncomeLossFromContinuingOperationsBeforeChangesInAccountingAndExtraordinaryItemsNetOfTaxPerShareDiluted |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Earnings Per Share, Basic | $ (0.02)us-gaap_EarningsPerShareBasic | $ 0.04 us-gaap_EarningsPerShareBasic | $ 0.00 us-gaap_EarningsPerShareBasic | $ (0.03)us-gaap_EarningsPerShareBasic | $ 0.12 us-gaap_EarningsPerShareBasic | $ 0.06 us-gaap_EarningsPerShareBasic | $ 0.03 us-gaap_EarningsPerShareBasic | $ 0.01 us-gaap_EarningsPerShareBasic | $ 0.00 us-gaap_EarningsPerShareBasic | $ 0.23 us-gaap_EarningsPerShareBasic | $ (0.06)us-gaap_EarningsPerShareBasic |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Pro Forma, Earnings Per Share, Basic |  |  |  |  |  |  |  |  |  | $ 0.17 us-gaap_BusinessAcquisitionProFormaEarningsPerShareBasic | $ (0.12)us-gaap_BusinessAcquisitionProFormaEarningsPerShareBasic |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Earnings Per Share, Diluted | $ (0.02)us-gaap_EarningsPerShareDiluted | $ 0.04 us-gaap_EarningsPerShareDiluted | $ 0.00 us-gaap_EarningsPerShareDiluted | $ (0.03)us-gaap_EarningsPerShareDiluted | $ 0.12 us-gaap_EarningsPerShareDiluted | $ 0.06 us-gaap_EarningsPerShareDiluted | $ 0.03 us-gaap_EarningsPerShareDiluted | $ 0.01 us-gaap_EarningsPerShareDiluted | $ 0.00 us-gaap_EarningsPerShareDiluted | $ 0.23 us-gaap_EarningsPerShareDiluted | $ (0.06)us-gaap_EarningsPerShareDiluted |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Pro Forma Earnings Per Share, Diluted |  |  |  |  |  |  |  |  |  | $ 0.17 us-gaap_BusinessAcquisitionProFormaEarningsPerShareDiluted | $ (0.12)us-gaap_BusinessAcquisitionProFormaEarningsPerShareDiluted |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Other assets | 65,111,000 us-gaap_OtherAssets |  |  |  | 62,377,000 us-gaap_OtherAssets |  |  |  | 65,111,000 us-gaap_OtherAssets | 62,377,000 us-gaap_OtherAssets |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
One and Two Commerce Square [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Significant Acquisitions and Disposals [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Property, Plant, and Equipment |  |  |  |  |  |  |  |  |  |  |  | 255,705,000 us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedPropertyPlantAndEquipment / us-gaap_SignificantAcquisitionsAndDisposalsByTransactionAxis = bdn_OneandTwoCommerceSquareMember |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Business Combination, Step Acquisition, Equity Interest in Acquiree, Percentage |  |  |  |  |  |  |  |  |  |  |  | 99.00%us-gaap_BusinessCombinationStepAcquisitionEquityInterestInAcquireeIncludingSubsequentAcquisitionPercentage / us-gaap_SignificantAcquisitionsAndDisposalsByTransactionAxis = bdn_OneandTwoCommerceSquareMember |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Net gain (loss) on sale of undepreciated real estate |  |  |  |  |  |  |  |  |  |  |  | 981,000 us-gaap_BusinessCombinationStepAcquisitionEquityInterestInAcquireeRemeasurementGain / us-gaap_SignificantAcquisitionsAndDisposalsByTransactionAxis = bdn_OneandTwoCommerceSquareMember |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of floors of a building |  |  |  |  |  |  |  |  |  |  |  | 41 bdn_NumberOfFloorsOfBuilding / us-gaap_SignificantAcquisitionsAndDisposalsByTransactionAxis = bdn_OneandTwoCommerceSquareMember |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Significant Acquisitions and Disposals, Acquisition Costs or Sale Proceeds |  |  |  |  |  |  |  |  |  |  |  | 331,800,000 us-gaap_BusinessCombinationConsiderationTransferred1 / us-gaap_SignificantAcquisitionsAndDisposalsByTransactionAxis = bdn_OneandTwoCommerceSquareMember |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Business Combination, Assumption of Existing Mortgage Debt |  |  |  |  |  |  |  |  |  |  |  | 237,100,000 bdn_BusinessCombinationAssumptionofExistingMortgageDebt / us-gaap_SignificantAcquisitionsAndDisposalsByTransactionAxis = bdn_OneandTwoCommerceSquareMember |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Lease percentage of acquired property |  |  |  |  | 86.70%bdn_LeasePercentageOfAcquiredProperty / us-gaap_SignificantAcquisitionsAndDisposalsByTransactionAxis = bdn_OneandTwoCommerceSquareMember |  |  |  |  | 86.70%bdn_LeasePercentageOfAcquiredProperty / us-gaap_SignificantAcquisitionsAndDisposalsByTransactionAxis = bdn_OneandTwoCommerceSquareMember |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Net rentable space of property acquired |  |  |  |  |  |  |  |  |  |  |  | 1,896,142 bdn_NetRentableSpace / us-gaap_SignificantAcquisitionsAndDisposalsByTransactionAxis = bdn_OneandTwoCommerceSquareMember |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Acquisition related costs |  |  |  |  |  |  |  |  |  |  |  | 900,000 us-gaap_BusinessAcquisitionCostOfAcquiredEntityTransactionCosts / us-gaap_SignificantAcquisitionsAndDisposalsByTransactionAxis = bdn_OneandTwoCommerceSquareMember |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Finite-Lived Intangibles |  |  |  |  |  |  |  |  |  |  |  | 85,036,000 us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedIntangibles / us-gaap_SignificantAcquisitionsAndDisposalsByTransactionAxis = bdn_OneandTwoCommerceSquareMember |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Noncurrent Liabilities, Other |  |  |  |  |  |  |  |  |  |  |  | (8,637,000)us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNoncurrentLiabilitiesOther / us-gaap_SignificantAcquisitionsAndDisposalsByTransactionAxis = bdn_OneandTwoCommerceSquareMember |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Net |  |  |  |  |  |  |  |  |  |  |  | 332,104,000 us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNet / us-gaap_SignificantAcquisitionsAndDisposalsByTransactionAxis = bdn_OneandTwoCommerceSquareMember |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Noncurrent Liabilities, Long-term Debt |  |  |  |  |  |  |  |  |  |  |  | (238,082,000)us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNoncurrentLiabilitiesLongTermDebt / us-gaap_SignificantAcquisitionsAndDisposalsByTransactionAxis = bdn_OneandTwoCommerceSquareMember |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Business Combination, return of capital on equity method investment |  |  |  |  |  |  |  |  |  |  |  | (30,424,000)bdn_BusinessCombinationreturnofcapitalonequitymethodinvestment / us-gaap_SignificantAcquisitionsAndDisposalsByTransactionAxis = bdn_OneandTwoCommerceSquareMember |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets, Other |  |  |  |  |  |  |  |  |  |  |  | 10,423,000 us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsOther / us-gaap_SignificantAcquisitionsAndDisposalsByTransactionAxis = bdn_OneandTwoCommerceSquareMember |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Business Combination, Acquisition of Less than 100 Percent, Noncontrolling Interest, Fair Value |  |  |  |  |  |  |  |  |  |  |  | (946,000)us-gaap_BusinessCombinationAcquisitionOfLessThan100PercentNoncontrollingInterestFairValue / us-gaap_SignificantAcquisitionsAndDisposalsByTransactionAxis = bdn_OneandTwoCommerceSquareMember |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Business Combination, Total Cash Payment at Settlement |  |  |  |  |  |  |  |  |  |  |  | 73,075,000 bdn_BusinessCombinationTotalCashPaymentatSettlement / us-gaap_SignificantAcquisitionsAndDisposalsByTransactionAxis = bdn_OneandTwoCommerceSquareMember |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Four Points Centre [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Significant Acquisitions and Disposals [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Area of Land |  |  |  |  |  |  |  |  |  |  |  | 22.3 us-gaap_AreaOfLand / us-gaap_SignificantAcquisitionsAndDisposalsByTransactionAxis = bdn_FourPointsCentreMember |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Significant Acquisitions and Disposals, Acquisition Costs or Sale Proceeds |  |  |  |  |  |  |  |  |  |  |  | 47,300,000 us-gaap_BusinessCombinationConsiderationTransferred1 / us-gaap_SignificantAcquisitionsAndDisposalsByTransactionAxis = bdn_FourPointsCentreMember |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Lease percentage of acquired property |  |  |  |  |  |  |  |  |  |  |  | 99.20%bdn_LeasePercentageOfAcquiredProperty / us-gaap_SignificantAcquisitionsAndDisposalsByTransactionAxis = bdn_FourPointsCentreMember |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Business Acquisition Purchase Price Allocation Intangible Assets |  |  |  |  |  |  |  |  |  |  |  | 6,500,000 bdn_BusinessAcquisitionPurchasePriceAllocationIntangibleAssets / us-gaap_SignificantAcquisitionsAndDisposalsByTransactionAxis = bdn_FourPointsCentreMember |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Business Acquisition Purchase Price Allocated To Market Lease Liabilities |  |  |  |  |  |  |  |  |  |  |  | 1,000,000 bdn_BusinessAcquisitionPurchasePriceAllocatedToMarketLeaseLiabilities / us-gaap_SignificantAcquisitionsAndDisposalsByTransactionAxis = bdn_FourPointsCentreMember |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Net rentable space of property acquired |  |  |  |  |  |  |  |  |  |  |  | 192,396 bdn_NetRentableSpace / us-gaap_SignificantAcquisitionsAndDisposalsByTransactionAxis = bdn_FourPointsCentreMember |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Acquisition related costs |  |  |  |  |  |  |  |  |  |  |  | 100,000 us-gaap_BusinessAcquisitionCostOfAcquiredEntityTransactionCosts / us-gaap_SignificantAcquisitionsAndDisposalsByTransactionAxis = bdn_FourPointsCentreMember |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Business Acquisition Purchase Price Allocation Building |  |  |  |  |  |  |  |  |  |  |  | 36,000,000 bdn_BusinessAcquisitionPurchasePriceAllocationBuilding / us-gaap_SignificantAcquisitionsAndDisposalsByTransactionAxis = bdn_FourPointsCentreMember |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Business Acquisition Purchase Price Allocation, Land Portion |  |  |  |  |  |  |  |  |  |  |  | 5,800,000 bdn_BusinessAcquisitionPurchasePriceAllocationLandPortion / us-gaap_SignificantAcquisitionsAndDisposalsByTransactionAxis = bdn_FourPointsCentreMember |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Cira Ground Land Parcel [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Significant Acquisitions and Disposals [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Area of Land |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 0.8 us-gaap_AreaOfLand / us-gaap_SignificantAcquisitionsAndDisposalsByTransactionAxis = bdn_CiraGroundLandParcelMember |  |  |  |  |  |
Ground Lease Buy-out, Total Cost |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 24,600,000 bdn_GroundLeaseBuyOutTotalCost / us-gaap_SignificantAcquisitionsAndDisposalsByTransactionAxis = bdn_CiraGroundLandParcelMember |  |  |  |  |  |
Accrued Rent |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 12,100,000 us-gaap_AccruedRentCurrentAndNoncurrent / us-gaap_SignificantAcquisitionsAndDisposalsByTransactionAxis = bdn_CiraGroundLandParcelMember |  |  |  |  |  |
Acquisition related costs |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 1,400,000 us-gaap_BusinessAcquisitionCostOfAcquiredEntityTransactionCosts / us-gaap_SignificantAcquisitionsAndDisposalsByTransactionAxis = bdn_CiraGroundLandParcelMember |  |  |  |  |  |
Rob Roy - Land [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Significant Acquisitions and Disposals [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Area of Land |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 16.8 us-gaap_AreaOfLand / us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis = bdn_RobRoyLandMember |  |  |  |  |
Sales price of properties sold |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 3,500,000 bdn_SaleConsiderationOfSoldProperty / us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis = bdn_RobRoyLandMember |  |  |  |  |
Net gain (loss) on sale of undepreciated real estate |  |  |  |  |  |  |  |  | 1,200,000 bdn_Netgainlossonsaleofundepreciatedrealestate / us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis = bdn_RobRoyLandMember |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
1000 Atrium Way and Libertyview [Member] [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Significant Acquisitions and Disposals [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of Real Estate Properties | 2 us-gaap_NumberOfRealEstateProperties / us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis = bdn_A1000AtriumWayandLibertyviewMemberMember |  |  |  |  |  |  |  | 2 us-gaap_NumberOfRealEstateProperties / us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis = bdn_A1000AtriumWayandLibertyviewMemberMember |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Valleybrooke Office Park [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Significant Acquisitions and Disposals [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Disposal group, number of properties held for sale | 5 bdn_Disposalgroupnumberofpropertiesheldforsale / us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis = bdn_ValleybrookeOfficeParkMember |  |  |  |  |  |  |  | 5 bdn_Disposalgroupnumberofpropertiesheldforsale / us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis = bdn_ValleybrookeOfficeParkMember |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Net rentable square feet of properties sold | 279,934 bdn_NetRentableSpaceSold / us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis = bdn_ValleybrookeOfficeParkMember |  |  |  |  |  |  |  | 279,934 bdn_NetRentableSpaceSold / us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis = bdn_ValleybrookeOfficeParkMember |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Sales price of properties sold | 37,900,000 bdn_SaleConsiderationOfSoldProperty / us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis = bdn_ValleybrookeOfficeParkMember |  |  |  |  |  |  |  | 37,900,000 bdn_SaleConsiderationOfSoldProperty / us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis = bdn_ValleybrookeOfficeParkMember |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Campus Pointe [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Significant Acquisitions and Disposals [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Disposal Group, Not Discontinued Operation, Gain (Loss) on Disposal |  |  |  |  |  |  |  |  | 4,700,000 us-gaap_DisposalGroupNotDiscontinuedOperationGainLossOnDisposal / us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis = bdn_CampusPointeMember |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Net rentable square feet of properties sold |  | 172,943 bdn_NetRentableSpaceSold / us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis = bdn_CampusPointeMember |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Sales price of properties sold |  | 42,500,000 bdn_SaleConsiderationOfSoldProperty / us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis = bdn_CampusPointeMember |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
West Point II Land [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Significant Acquisitions and Disposals [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Area of Land |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 5.3 us-gaap_AreaOfLand / us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis = bdn_WestPointIILandMember |  |  |  |
Sales price of properties sold |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 1,600,000 bdn_SaleConsiderationOfSoldProperty / us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis = bdn_WestPointIILandMember |  |  |  |
1000 Atrium Way [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Significant Acquisitions and Disposals [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Net rentable space of property acquired | 99,668 bdn_NetRentableSpace / us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis = bdn_A1000AtriumWayMember |  |  |  |  |  |  |  | 99,668 bdn_NetRentableSpace / us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis = bdn_A1000AtriumWayMember |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
875 First Avenue [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Significant Acquisitions and Disposals [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Gain (Loss) on Sale of Properties |  |  |  |  |  |  |  |  |  |  |  | 100,000 us-gaap_DiscontinuedOperationGainLossOnDisposalOfDiscontinuedOperationNetOfTax / us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis = bdn_A875FirstAvenueMember |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Net rentable square feet of properties sold |  |  |  |  |  |  |  |  |  |  |  | 50,000 bdn_NetRentableSpaceSold / us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis = bdn_A875FirstAvenueMember |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Sales price of properties sold |  |  |  |  |  |  |  |  |  |  |  | 3,800,000 bdn_SaleConsiderationOfSoldProperty / us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis = bdn_A875FirstAvenueMember |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
1336 Enterprise Drive [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Significant Acquisitions and Disposals [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Gain (Loss) on Sale of Properties |  |  |  |  |  |  |  |  |  |  |  |  | 200,000 us-gaap_DiscontinuedOperationGainLossOnDisposalOfDiscontinuedOperationNetOfTax / us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis = bdn_A1336EnterpriseDriveMember |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Net rentable square feet of properties sold |  |  |  |  |  |  |  |  |  |  |  |  | 39,330 bdn_NetRentableSpaceSold / us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis = bdn_A1336EnterpriseDriveMember |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Sales price of properties sold |  |  |  |  |  |  |  |  |  |  |  |  | 2,600,000 bdn_SaleConsiderationOfSoldProperty / us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis = bdn_A1336EnterpriseDriveMember |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Dabney Land, East [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Significant Acquisitions and Disposals [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Area of Land |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 8 us-gaap_AreaOfLand / us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis = bdn_DabneyLandEastMember |  |  |
Sales price of properties sold |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 500,000 bdn_SaleConsiderationOfSoldProperty / us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis = bdn_DabneyLandEastMember |  |  |
Net gain (loss) on sale of undepreciated real estate |  |  |  |  |  |  |  |  |  | (100,000)bdn_Netgainlossonsaleofundepreciatedrealestate / us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis = bdn_DabneyLandEastMember |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Pacific View Plaza [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Significant Acquisitions and Disposals [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Gain (Loss) on Sale of Properties |  |  |  |  |  |  |  |  |  |  |  |  |  | (500,000)us-gaap_DiscontinuedOperationGainLossOnDisposalOfDiscontinuedOperationNetOfTax / us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis = bdn_PacificViewPlazaMember |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Net rentable square feet of properties sold |  |  |  |  |  |  |  |  |  |  |  |  |  | 51,695 bdn_NetRentableSpaceSold / us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis = bdn_PacificViewPlazaMember |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Sales price of properties sold |  |  |  |  |  |  |  |  |  |  |  |  |  | 10,300,000 bdn_SaleConsiderationOfSoldProperty / us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis = bdn_PacificViewPlazaMember |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Princeton Pike Corporate Center [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Significant Acquisitions and Disposals [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Gain (Loss) on Sale of Properties |  |  |  |  |  |  |  |  |  | 5,300,000 us-gaap_DiscontinuedOperationGainLossOnDisposalOfDiscontinuedOperationNetOfTax / us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis = bdn_PrincetonPikeCorporateCenterMember |  |  |  |  | 900,000 us-gaap_DiscontinuedOperationGainLossOnDisposalOfDiscontinuedOperationNetOfTax / us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis = bdn_PrincetonPikeCorporateCenterMember |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of flex/office properties sold |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 8 bdn_NumberOfRealEstatePropertiesSold / us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis = bdn_PrincetonPikeCorporateCenterMember |  |
Net rentable square feet of properties sold |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 800,546 bdn_NetRentableSpaceSold / us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis = bdn_PrincetonPikeCorporateCenterMember |  |
Sales price of properties sold |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 121,000,000 bdn_SaleConsiderationOfSoldProperty / us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis = bdn_PrincetonPikeCorporateCenterMember |  |
Oaklands Corporate Center [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Significant Acquisitions and Disposals [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Gain (Loss) on Sale of Properties |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 9,900,000 us-gaap_DiscontinuedOperationGainLossOnDisposalOfDiscontinuedOperationNetOfTax / us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis = bdn_OaklandsCorporateCenterMember |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of flex/office properties sold |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 11 bdn_NumberOfRealEstatePropertiesSold / us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis = bdn_OaklandsCorporateCenterMember |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Net rentable square feet of properties sold |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 466,719 bdn_NetRentableSpaceSold / us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis = bdn_OaklandsCorporateCenterMember |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Sales price of properties sold |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 52,700,000 bdn_SaleConsiderationOfSoldProperty / us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis = bdn_OaklandsCorporateCenterMember |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Pacific Ridge Corporate Center [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Significant Acquisitions and Disposals [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Gain (Loss) on Sale of Properties |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | (2,800,000)us-gaap_DiscontinuedOperationGainLossOnDisposalOfDiscontinuedOperationNetOfTax / us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis = bdn_PacificRidgeCorporateCenterMember |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Net rentable square feet of properties sold |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 121,381 bdn_NetRentableSpaceSold / us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis = bdn_PacificRidgeCorporateCenterMember |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Sales price of properties sold |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 29,000,000 bdn_SaleConsiderationOfSoldProperty / us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis = bdn_PacificRidgeCorporateCenterMember |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
South Lake at Dulles Corner [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Significant Acquisitions and Disposals [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Gain (Loss) on Sale of Properties |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 14,500,000 us-gaap_DiscontinuedOperationGainLossOnDisposalOfDiscontinuedOperationNetOfTax / us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis = bdn_SouthLakeAtDullusCornerMember |  |  |  |  |  |  |  |  |  |  |  |  |  |
Net rentable square feet of properties sold |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 268,240 bdn_NetRentableSpaceSold / us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis = bdn_SouthLakeAtDullusCornerMember |  |  |  |  |  |  |  |  |  |  |  |  |  |
Sales price of properties sold |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 91,100,000 bdn_SaleConsiderationOfSoldProperty / us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis = bdn_SouthLakeAtDullusCornerMember |  |  |  |  |  |  |  |  |  |  |  |  |  |
304 Harper Drive [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Significant Acquisitions and Disposals [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Gain (Loss) on Sale of Properties |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 200,000 us-gaap_DiscontinuedOperationGainLossOnDisposalOfDiscontinuedOperationNetOfTax / us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis = bdn_A304HarperDriveMember |  |  |  |  |  |  |  |  |  |  |  |  |
Net rentable square feet of properties sold |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 32,978 bdn_NetRentableSpaceSold / us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis = bdn_A304HarperDriveMember |  |  |  |  |  |  |  |  |  |  |  |  |
Sales price of properties sold |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 3,000,000 bdn_SaleConsiderationOfSoldProperty / us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis = bdn_A304HarperDriveMember |  |  |  |  |  |  |  |  |  |  |  |  |
The Bluffs [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Significant Acquisitions and Disposals [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Gain (Loss) on Sale of Properties |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | (900,000)us-gaap_DiscontinuedOperationGainLossOnDisposalOfDiscontinuedOperationNetOfTax / us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis = bdn_BluffsMember |  |  |  |  |  |  |  |  |  |  |  |
Net rentable square feet of properties sold |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 68,708 bdn_NetRentableSpaceSold / us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis = bdn_BluffsMember |  |  |  |  |  |  |  |  |  |  |  |
Sales price of properties sold |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 18,000,000 bdn_SaleConsiderationOfSoldProperty / us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis = bdn_BluffsMember |  |  |  |  |  |  |  |  |  |  |  |
100 Arrandale Boulevard [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Significant Acquisitions and Disposals [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Gain (Loss) on Sale of Properties |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | (400,000)us-gaap_DiscontinuedOperationGainLossOnDisposalOfDiscontinuedOperationNetOfTax / us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis = bdn_A100ArrandaleBoulevardMember |  |  |  |  |  |  |  |  |  |  |  |
Net rentable square feet of properties sold |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 34,931 bdn_NetRentableSpaceSold / us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis = bdn_A100ArrandaleBoulevardMember |  |  |  |  |  |  |  |  |  |  |  |
Sales price of properties sold |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 3,500,000 bdn_SaleConsiderationOfSoldProperty / us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis = bdn_A100ArrandaleBoulevardMember |  |  |  |  |  |  |  |  |  |  |  |
1700 Paoli Pike [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Significant Acquisitions and Disposals [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Gain (Loss) on Sale of Properties |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | (400,000)us-gaap_DiscontinuedOperationGainLossOnDisposalOfDiscontinuedOperationNetOfTax / us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis = bdn_A1700PaoliPikeMember |  |  |  |  |  |  |  |  |  |  |
Net rentable square feet of properties sold |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 28,000 bdn_NetRentableSpaceSold / us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis = bdn_A1700PaoliPikeMember |  |  |  |  |  |  |  |  |  |  |
Sales price of properties sold |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 2,700,000 bdn_SaleConsiderationOfSoldProperty / us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis = bdn_A1700PaoliPikeMember |  |  |  |  |  |  |  |  |  |  |
Four Points Centre [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Significant Acquisitions and Disposals [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of floors of a building |  |  |  |  |  |  |  |  |  |  |  | 3 bdn_NumberOfFloorsOfBuilding / us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis = bdn_FourPointsCentreMember |  |  |  |  |  |  |  |  |  |  |  | 3 bdn_NumberOfFloorsOfBuilding / us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis = bdn_FourPointsCentreMember |  |  |  |  |  |  |  |
Net rentable space of property acquired |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 192,396 bdn_NetRentableSpace / us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis = bdn_FourPointsCentreMember |  |  |  |  |  |  |  |
Number of Real Estate Properties |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 2 us-gaap_NumberOfRealEstateProperties / us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis = bdn_FourPointsCentreMember |  |  |  |  |  |  |  |
Libertyview [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Significant Acquisitions and Disposals [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Net rentable space of property acquired | 121,737 bdn_NetRentableSpace / us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis = bdn_LibertyviewMember |  |  |  |  |  |  |  | 121,737 bdn_NetRentableSpace / us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis = bdn_LibertyviewMember |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Austin Joint Venture [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Significant Acquisitions and Disposals [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Equity Method Investments | 40,374,000 us-gaap_EquityMethodInvestments / us-gaap_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis = bdn_AustinJointVentureMember |  |  |  |  |  |  |  | 40,374,000 us-gaap_EquityMethodInvestments / us-gaap_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis = bdn_AustinJointVentureMember |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Company's Ownership Percentage in the Real Estate Venture | 50.00%us-gaap_EquityMethodInvestmentOwnershipPercentage / us-gaap_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis = bdn_AustinJointVentureMember |  |  |  |  |  |  |  | 50.00%us-gaap_EquityMethodInvestmentOwnershipPercentage / us-gaap_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis = bdn_AustinJointVentureMember |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Net rentable space of property acquired |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 590,881 bdn_NetRentableSpace / us-gaap_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis = bdn_AustinJointVentureMember |
Number of Real Estate Properties |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 7 us-gaap_NumberOfRealEstateProperties / us-gaap_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis = bdn_AustinJointVentureMember | 2 us-gaap_NumberOfRealEstateProperties / us-gaap_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis = bdn_AustinJointVentureMember
Austin Joint Venture [Member] | Four Points Centre [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Significant Acquisitions and Disposals [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Non-Recourse Debt |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 29,000,000 us-gaap_NonRecourseDebt / us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis = bdn_FourPointsCentreMember / us-gaap_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis = bdn_AustinJointVentureMember |  |  |  |  |  |  |  |
Brandywine - Al Venture [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Significant Acquisitions and Disposals [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Equity Method Investments | 45,712,000 us-gaap_EquityMethodInvestments / us-gaap_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis = bdn_BrandywineAlVentureMember |  |  |  |  |  |  |  | 45,712,000 us-gaap_EquityMethodInvestments / us-gaap_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis = bdn_BrandywineAlVentureMember |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Company's Ownership Percentage in the Real Estate Venture | 50.00%us-gaap_EquityMethodInvestmentOwnershipPercentage / us-gaap_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis = bdn_BrandywineAlVentureMember |  |  |  |  |  |  |  | 50.00%us-gaap_EquityMethodInvestmentOwnershipPercentage / us-gaap_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis = bdn_BrandywineAlVentureMember |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Encino Trace - Land [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Significant Acquisitions and Disposals [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of potential development properties |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 2 bdn_Numberofpotentialdevelopmentproperties / us-gaap_BusinessAcquisitionAxis = bdn_EncinoTraceLandMember |  |  |  |  |  |  |  |  |  |
Number of floors of a building |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 4 bdn_NumberOfFloorsOfBuilding / us-gaap_BusinessAcquisitionAxis = bdn_EncinoTraceLandMember |  |  |  |  |  |  |  |  |  |
Significant Acquisitions and Disposals, Acquisition Costs or Sale Proceeds |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 14,000,000 us-gaap_BusinessCombinationConsiderationTransferred1 / us-gaap_BusinessAcquisitionAxis = bdn_EncinoTraceLandMember |  |  |  |  |  |  |  |  |  |
Total potential development capacity |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 320,000 bdn_TotalPotentialDevelopmentCapacity / us-gaap_BusinessAcquisitionAxis = bdn_EncinoTraceLandMember |  |  |  |  |  |  |  |  |  |
Land |  |  | 4,600,000 us-gaap_Land / us-gaap_BusinessAcquisitionAxis = bdn_EncinoTraceLandMember |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Escrow Deposit |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 1,000,000 us-gaap_EscrowDeposit / us-gaap_BusinessAcquisitionAxis = bdn_EncinoTraceLandMember |  |  |  |  |  |  |  |  |  |
Construction in Progress, Gross |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 8,400,000 us-gaap_ConstructionInProgressGross / us-gaap_BusinessAcquisitionAxis = bdn_EncinoTraceLandMember |  |  |  |  |  |  |  |  |  |
Lease percentage of acquired property |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 75.00%bdn_LeasePercentageOfAcquiredProperty / us-gaap_BusinessAcquisitionAxis = bdn_EncinoTraceLandMember |  |  |  |  |  |  |  |  |  |
Area Owned by Company of Undeveloped Parcels Of Land |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 54.1 bdn_AreaOwnedbyCompanyofUndevelopedParcelsOfLand / us-gaap_BusinessAcquisitionAxis = bdn_EncinoTraceLandMember |  |  |  |  |  |  |  |  |  |
Three Logan Square [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Significant Acquisitions and Disposals [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Area of Land |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 1.8 us-gaap_AreaOfLand / us-gaap_BusinessAcquisitionAxis = bdn_ThreeLoganSquareMember |  |  |  |  |  |  |  |  |
Ground Lease Buy-out, Total Cost |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 20,800,000 bdn_GroundLeaseBuyOutTotalCost / us-gaap_BusinessAcquisitionAxis = bdn_ThreeLoganSquareMember |  |  |  |  |  |  |  |  |
Adjustment to Record Land Acquisition to Fair Value |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 4,300,000 bdn_AdjustmenttoRecordLandAcquisitiontoFairValue / us-gaap_BusinessAcquisitionAxis = bdn_ThreeLoganSquareMember |  |  |  |  |  |  |  |  |
Acquisition related costs |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 100,000 us-gaap_BusinessAcquisitionCostOfAcquiredEntityTransactionCosts / us-gaap_BusinessAcquisitionAxis = bdn_ThreeLoganSquareMember |  |  |  |  |  |  |  |  |
Secured Debt [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Significant Acquisitions and Disposals [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Long-term Debt, Gross | 655,934,000 us-gaap_DebtInstrumentCarryingAmount / us-gaap_LongtermDebtTypeAxis = us-gaap_SecuredDebtMember |  |  |  | 669,762,000 us-gaap_DebtInstrumentCarryingAmount / us-gaap_LongtermDebtTypeAxis = us-gaap_SecuredDebtMember |  |  |  | 655,934,000 us-gaap_DebtInstrumentCarryingAmount / us-gaap_LongtermDebtTypeAxis = us-gaap_SecuredDebtMember | 669,762,000 us-gaap_DebtInstrumentCarryingAmount / us-gaap_LongtermDebtTypeAxis = us-gaap_SecuredDebtMember |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Secured Debt | 654,590,000 us-gaap_SecuredDebt / us-gaap_LongtermDebtTypeAxis = us-gaap_SecuredDebtMember |  |  |  | 670,151,000 us-gaap_SecuredDebt / us-gaap_LongtermDebtTypeAxis = us-gaap_SecuredDebtMember |  |  |  | 654,590,000 us-gaap_SecuredDebt / us-gaap_LongtermDebtTypeAxis = us-gaap_SecuredDebtMember | 670,151,000 us-gaap_SecuredDebt / us-gaap_LongtermDebtTypeAxis = us-gaap_SecuredDebtMember |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Secured Debt [Member] | Two Commerce Square [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Significant Acquisitions and Disposals [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Long-term Debt, Percentage Bearing Fixed Interest, Percentage Rate |  |  |  |  |  |  |  |  |  |  |  | 3.96%us-gaap_LongTermDebtPercentageBearingFixedInterestRate / us-gaap_LongtermDebtTypeAxis = us-gaap_SecuredDebtMember / us-gaap_SignificantAcquisitionsAndDisposalsByTransactionAxis = bdn_TwoCommerceSquareMember |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Long-term Debt, Fair Value |  |  |  |  |  |  |  |  |  |  |  | 107,900,000 us-gaap_LongTermDebtFairValue / us-gaap_LongtermDebtTypeAxis = us-gaap_SecuredDebtMember / us-gaap_SignificantAcquisitionsAndDisposalsByTransactionAxis = bdn_TwoCommerceSquareMember |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Long-term Debt, Gross |  |  |  |  |  |  |  |  |  |  |  | 112,000,000 us-gaap_DebtInstrumentCarryingAmount / us-gaap_LongtermDebtTypeAxis = us-gaap_SecuredDebtMember / us-gaap_SignificantAcquisitionsAndDisposalsByTransactionAxis = bdn_TwoCommerceSquareMember |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Secured Debt [Member] | One Commerce Square [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Significant Acquisitions and Disposals [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Long-term Debt, Percentage Bearing Fixed Interest, Percentage Rate |  |  |  |  |  |  |  |  |  |  |  | 5.67%us-gaap_LongTermDebtPercentageBearingFixedInterestRate / us-gaap_LongtermDebtTypeAxis = us-gaap_SecuredDebtMember / us-gaap_SignificantAcquisitionsAndDisposalsByTransactionAxis = bdn_OneCommerceSquareMember |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Long-term Debt, Fair Value |  |  |  |  |  |  |  |  |  |  |  | 130,200,000 us-gaap_LongTermDebtFairValue / us-gaap_LongtermDebtTypeAxis = us-gaap_SecuredDebtMember / us-gaap_SignificantAcquisitionsAndDisposalsByTransactionAxis = bdn_OneCommerceSquareMember |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Long-term Debt, Gross |  |  |  |  |  |  |  |  |  |  |  | 125,100,000 us-gaap_DebtInstrumentCarryingAmount / us-gaap_LongtermDebtTypeAxis = us-gaap_SecuredDebtMember / us-gaap_SignificantAcquisitionsAndDisposalsByTransactionAxis = bdn_OneCommerceSquareMember |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Subsidiaries [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Significant Acquisitions and Disposals [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Provision for impairment on assets held for sale |  |  |  |  |  |  |  |  | 1,765,000 us-gaap_ImpairmentOfLongLivedAssetsToBeDisposedOf / dei_LegalEntityAxis = us-gaap_SubsidiariesMember | 0 us-gaap_ImpairmentOfLongLivedAssetsToBeDisposedOf / dei_LegalEntityAxis = us-gaap_SubsidiariesMember | 0 us-gaap_ImpairmentOfLongLivedAssetsToBeDisposedOf / dei_LegalEntityAxis = us-gaap_SubsidiariesMember |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Net gain (loss) on sale of undepreciated real estate |  |  |  |  |  |  |  |  | 458,000 us-gaap_BusinessCombinationStepAcquisitionEquityInterestInAcquireeRemeasurementGain / dei_LegalEntityAxis = us-gaap_SubsidiariesMember | 6,866,000 us-gaap_BusinessCombinationStepAcquisitionEquityInterestInAcquireeRemeasurementGain / dei_LegalEntityAxis = us-gaap_SubsidiariesMember | 0 us-gaap_BusinessCombinationStepAcquisitionEquityInterestInAcquireeRemeasurementGain / dei_LegalEntityAxis = us-gaap_SubsidiariesMember |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Adjustment to Record Land Acquisition to Fair Value |  |  |  |  |  |  |  |  | 0 bdn_AdjustmenttoRecordLandAcquisitiontoFairValue / dei_LegalEntityAxis = us-gaap_SubsidiariesMember | 7,752,000 bdn_AdjustmenttoRecordLandAcquisitiontoFairValue / dei_LegalEntityAxis = us-gaap_SubsidiariesMember |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Payments to Acquire Real Estate |  |  |  |  |  |  |  |  | 18,443,000 us-gaap_PaymentsToAcquireRealEstate / dei_LegalEntityAxis = us-gaap_SubsidiariesMember | 161,604,000 us-gaap_PaymentsToAcquireRealEstate / dei_LegalEntityAxis = us-gaap_SubsidiariesMember | 77,555,000 us-gaap_PaymentsToAcquireRealEstate / dei_LegalEntityAxis = us-gaap_SubsidiariesMember |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Gains (Losses) on Sales of Investment Real Estate |  |  |  |  |  |  |  |  | 4,901,000 us-gaap_GainsLossesOnSalesOfInvestmentRealEstate / dei_LegalEntityAxis = us-gaap_SubsidiariesMember | 0 us-gaap_GainsLossesOnSalesOfInvestmentRealEstate / dei_LegalEntityAxis = us-gaap_SubsidiariesMember | 0 us-gaap_GainsLossesOnSalesOfInvestmentRealEstate / dei_LegalEntityAxis = us-gaap_SubsidiariesMember |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Equity Method Investments | 225,004,000 us-gaap_EquityMethodInvestments / dei_LegalEntityAxis = us-gaap_SubsidiariesMember |  |  |  | 180,512,000 us-gaap_EquityMethodInvestments / dei_LegalEntityAxis = us-gaap_SubsidiariesMember |  |  |  | 225,004,000 us-gaap_EquityMethodInvestments / dei_LegalEntityAxis = us-gaap_SubsidiariesMember | 180,512,000 us-gaap_EquityMethodInvestments / dei_LegalEntityAxis = us-gaap_SubsidiariesMember |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Secured Debt | 654,590,000 us-gaap_SecuredDebt / dei_LegalEntityAxis = us-gaap_SubsidiariesMember |  |  |  | 670,151,000 us-gaap_SecuredDebt / dei_LegalEntityAxis = us-gaap_SubsidiariesMember |  |  |  | 654,590,000 us-gaap_SecuredDebt / dei_LegalEntityAxis = us-gaap_SubsidiariesMember | 670,151,000 us-gaap_SecuredDebt / dei_LegalEntityAxis = us-gaap_SubsidiariesMember |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Balance of the Financing Obligation | 37,558,000 us-gaap_OtherLiabilities / dei_LegalEntityAxis = us-gaap_SubsidiariesMember |  |  |  | 32,923,000 us-gaap_OtherLiabilities / dei_LegalEntityAxis = us-gaap_SubsidiariesMember |  |  |  | 37,558,000 us-gaap_OtherLiabilities / dei_LegalEntityAxis = us-gaap_SubsidiariesMember | 32,923,000 us-gaap_OtherLiabilities / dei_LegalEntityAxis = us-gaap_SubsidiariesMember |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Gain (Loss) on Sale of Properties |  |  |  |  |  |  |  |  | 900,000 us-gaap_DiscontinuedOperationGainLossOnDisposalOfDiscontinuedOperationNetOfTax / dei_LegalEntityAxis = us-gaap_SubsidiariesMember | 3,382,000 us-gaap_DiscontinuedOperationGainLossOnDisposalOfDiscontinuedOperationNetOfTax / dei_LegalEntityAxis = us-gaap_SubsidiariesMember | 34,774,000 us-gaap_DiscontinuedOperationGainLossOnDisposalOfDiscontinuedOperationNetOfTax / dei_LegalEntityAxis = us-gaap_SubsidiariesMember |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Net gain (loss) on real estate venture transactions |  |  |  |  |  |  |  |  | (417,000)bdn_NetGainLossOnRealEstateVentureTransactionsincludingrealestateventureformation / dei_LegalEntityAxis = us-gaap_SubsidiariesMember | 3,683,000 bdn_NetGainLossOnRealEstateVentureTransactionsincludingrealestateventureformation / dei_LegalEntityAxis = us-gaap_SubsidiariesMember | 0 bdn_NetGainLossOnRealEstateVentureTransactionsincludingrealestateventureformation / dei_LegalEntityAxis = us-gaap_SubsidiariesMember |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Net gain (loss) on sale of undepreciated real estate |  |  |  |  |  |  |  |  | 1,184,000 bdn_Netgainlossonsaleofundepreciatedrealestate / dei_LegalEntityAxis = us-gaap_SubsidiariesMember | (137,000)bdn_Netgainlossonsaleofundepreciatedrealestate / dei_LegalEntityAxis = us-gaap_SubsidiariesMember | 0 bdn_Netgainlossonsaleofundepreciatedrealestate / dei_LegalEntityAxis = us-gaap_SubsidiariesMember |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Continuing operations (in dollars per share) |  |  |  |  |  |  |  |  | $ (0.01)us-gaap_IncomeLossFromContinuingOperationsPerBasicShare / dei_LegalEntityAxis = us-gaap_SubsidiariesMember | $ 0.20 us-gaap_IncomeLossFromContinuingOperationsPerBasicShare / dei_LegalEntityAxis = us-gaap_SubsidiariesMember | $ (0.36)us-gaap_IncomeLossFromContinuingOperationsPerBasicShare / dei_LegalEntityAxis = us-gaap_SubsidiariesMember |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Income (Loss) from Continuing Operations, Per Diluted Share |  |  |  |  |  |  |  |  | $ (0.01)us-gaap_IncomeLossFromContinuingOperationsPerDilutedShare / dei_LegalEntityAxis = us-gaap_SubsidiariesMember | $ 0.20 us-gaap_IncomeLossFromContinuingOperationsPerDilutedShare / dei_LegalEntityAxis = us-gaap_SubsidiariesMember | $ (0.36)us-gaap_IncomeLossFromContinuingOperationsPerDilutedShare / dei_LegalEntityAxis = us-gaap_SubsidiariesMember |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Earnings Per Share, Basic |  |  |  |  |  |  |  |  | $ 0.00 us-gaap_EarningsPerShareBasic / dei_LegalEntityAxis = us-gaap_SubsidiariesMember | $ 0.23 us-gaap_EarningsPerShareBasic / dei_LegalEntityAxis = us-gaap_SubsidiariesMember | $ (0.06)us-gaap_EarningsPerShareBasic / dei_LegalEntityAxis = us-gaap_SubsidiariesMember |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Earnings Per Share, Diluted |  |  |  |  |  |  |  |  | $ 0.00 us-gaap_EarningsPerShareDiluted / dei_LegalEntityAxis = us-gaap_SubsidiariesMember | $ 0.23 us-gaap_EarningsPerShareDiluted / dei_LegalEntityAxis = us-gaap_SubsidiariesMember | $ (0.06)us-gaap_EarningsPerShareDiluted / dei_LegalEntityAxis = us-gaap_SubsidiariesMember |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Other assets | 65,111,000 us-gaap_OtherAssets / dei_LegalEntityAxis = us-gaap_SubsidiariesMember |  |  |  | 62,377,000 us-gaap_OtherAssets / dei_LegalEntityAxis = us-gaap_SubsidiariesMember |  |  |  | 65,111,000 us-gaap_OtherAssets / dei_LegalEntityAxis = us-gaap_SubsidiariesMember | 62,377,000 us-gaap_OtherAssets / dei_LegalEntityAxis = us-gaap_SubsidiariesMember |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Brandywine Realty Trust [Member] | Austin Joint Venture [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Significant Acquisitions and Disposals [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Company's Ownership Percentage in the Real Estate Venture | 50.00%us-gaap_EquityMethodInvestmentOwnershipPercentage / bdn_JointVentureMembersAxis = bdn_BrandywineRealtyTrustMember / us-gaap_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis = bdn_AustinJointVentureMember |  |  |  |  |  |  |  | 50.00%us-gaap_EquityMethodInvestmentOwnershipPercentage / bdn_JointVentureMembersAxis = bdn_BrandywineRealtyTrustMember / us-gaap_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis = bdn_AustinJointVentureMember |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Aggregate gross sales price of a joint venture |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 330,000,000 bdn_Aggregategrosssalespriceofajointventure / bdn_JointVentureMembersAxis = bdn_BrandywineRealtyTrustMember / us-gaap_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis = bdn_AustinJointVentureMember |  |  |  |  |  |  |
Brandywine Realty Trust [Member] | Austin Joint Venture [Member] | Four Points Centre [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Significant Acquisitions and Disposals [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Aggregate gross sales price of a joint venture |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 41,500,000 bdn_Aggregategrosssalespriceofajointventure / us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis = bdn_FourPointsCentreMember / bdn_JointVentureMembersAxis = bdn_BrandywineRealtyTrustMember / us-gaap_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis = bdn_AustinJointVentureMember |  |  |  |  |  |  |  |
Amount Of Participant Contribution |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 5,900,000 bdn_AmountOfParticipantContribution / us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis = bdn_FourPointsCentreMember / bdn_JointVentureMembersAxis = bdn_BrandywineRealtyTrustMember / us-gaap_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis = bdn_AustinJointVentureMember |  |  |  |  |  |  |  |
Net gain (loss) on real estate venture transactions |  |  |  |  |  |  |  |  | (200,000)bdn_NetGainLossOnRealEstateVentureTransactionsincludingrealestateventureformation / us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis = bdn_FourPointsCentreMember / bdn_JointVentureMembersAxis = bdn_BrandywineRealtyTrustMember / us-gaap_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis = bdn_AustinJointVentureMember |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Proceeds from Equity Method Investment, Dividends or Distributions |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 34,400,000 us-gaap_EquityMethodInvestmentDividendsOrDistributions / us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis = bdn_FourPointsCentreMember / bdn_JointVentureMembersAxis = bdn_BrandywineRealtyTrustMember / us-gaap_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis = bdn_AustinJointVentureMember |  |  |  |  |  |  |  |
DRA Advisors LLC [Member] | Austin Joint Venture [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Significant Acquisitions and Disposals [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Company's Ownership Percentage in the Real Estate Venture | 50.00%us-gaap_EquityMethodInvestmentOwnershipPercentage / bdn_JointVentureMembersAxis = bdn_DRAAdvisorsLLCMember / us-gaap_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis = bdn_AustinJointVentureMember |  |  |  |  |  |  |  | 50.00%us-gaap_EquityMethodInvestmentOwnershipPercentage / bdn_JointVentureMembersAxis = bdn_DRAAdvisorsLLCMember / us-gaap_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis = bdn_AustinJointVentureMember |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Non-Recourse Debt |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 230,600,000 us-gaap_NonRecourseDebt / bdn_JointVentureMembersAxis = bdn_DRAAdvisorsLLCMember / us-gaap_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis = bdn_AustinJointVentureMember |  |  |  |  |  |  |
Amount Of Participant Contribution |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 49,700,000 bdn_AmountOfParticipantContribution / bdn_JointVentureMembersAxis = bdn_DRAAdvisorsLLCMember / us-gaap_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis = bdn_AustinJointVentureMember |  |  |  |  |  |  |
Proceeds from Equity Method Investment, Dividends or Distributions |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 271,500,000 us-gaap_EquityMethodInvestmentDividendsOrDistributions / bdn_JointVentureMembersAxis = bdn_DRAAdvisorsLLCMember / us-gaap_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis = bdn_AustinJointVentureMember |  |  |  |  |  |  |
DRA Advisors LLC [Member] | Austin Joint Venture [Member] | Four Points Centre [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Significant Acquisitions and Disposals [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Amount Of Participant Contribution |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 5,900,000 bdn_AmountOfParticipantContribution / us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis = bdn_FourPointsCentreMember / bdn_JointVentureMembersAxis = bdn_DRAAdvisorsLLCMember / us-gaap_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis = bdn_AustinJointVentureMember |  |  |  |  |  |  |  |
Encino Trace - Building I [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Significant Acquisitions and Disposals [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Construction in Progress, Gross | 38,800,000 us-gaap_ConstructionInProgressGross / bdn_DevelopmentProjectAxis = bdn_EncinoTraceBuildingIMember |  |  |  |  |  |  |  | 38,800,000 us-gaap_ConstructionInProgressGross / bdn_DevelopmentProjectAxis = bdn_EncinoTraceBuildingIMember |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Valleybrooke Office Park [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Significant Acquisitions and Disposals [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Provision for impairment on assets held for sale |  |  |  |  |  |  |  |  | 1,765,000 us-gaap_ImpairmentOfLongLivedAssetsToBeDisposedOf / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = bdn_ValleybrookeOfficeParkMember |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Gains (Losses) on Sales of Investment Real Estate |  |  |  |  |  |  |  |  | $ 200,000 us-gaap_GainsLossesOnSalesOfInvestmentRealEstate / us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis = bdn_ValleybrookeOfficeParkMember |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |

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- Definition Carrying value as of the balance sheet date of obligations incurred through that date and payable for contractual rent under lease arrangements. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.15(5)) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 15 -Subparagraph a -Article 7 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 15 -Subparagraph 5 -Article 9 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.15(5)) -URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910 + Details
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- Definition The pro forma basic net income per share for a period as if the business combination or combinations had been completed at the beginning of a period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (h)(2)-(3) -URI http://asc.fasb.org/extlink&oid=25497992&loc=d3e1392-128463 + Details
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- Definition The pro forma income from continuing operations before changes in accounting and extraordinary items, net of tax effect, for the period as if the business combination or combinations had been completed at the beginning of a period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (h)(2)-(3) -URI http://asc.fasb.org/extlink&oid=25497992&loc=d3e1392-128463 + Details
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- Definition The pro forma net Income or Loss for the period as if the business combination or combinations had been completed at the beginning of a period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (h)(2)-(3) -URI http://asc.fasb.org/extlink&oid=25497992&loc=d3e1392-128463 + Details
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- Definition The pro forma revenue for a period as if the business combination or combinations had been completed at the beginning of the period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (h)(2)-(3) -URI http://asc.fasb.org/extlink&oid=25497992&loc=d3e1392-128463 + Details
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- Definition This element represents the fair value of the noncontrolling interest in the acquiree at the acquisition date. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (e)(1) -URI http://asc.fasb.org/extlink&oid=39739317&loc=d3e4845-128472 + Details
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- Definition Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 30 -Section 30 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=6911251&loc=d3e6578-128477 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 30 -Section 30 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=6911251&loc=d3e6613-128477 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 30 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=35744584&loc=d3e6927-128479 + Details
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- Definition This element represents the amount of earnings or loss of the acquiree since the acquisition date included in the consolidated income statement for the reporting period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (h)(1) -URI http://asc.fasb.org/extlink&oid=25497992&loc=d3e1392-128463 + Details
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- Definition This element represents the amount of revenue of the acquiree since the acquisition date included in the consolidated income statement for the reporting period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (h)(1) -URI http://asc.fasb.org/extlink&oid=25497992&loc=d3e1392-128463 + Details
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- Definition Amount of other assets expected to be realized or consumed before one year or the normal operating cycle, if longer, acquired at the acquisition date. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=39739317&loc=d3e4845-128472 + Details
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- Definition The amount of identifiable intangible assets recognized as of the acquisition date. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=39739317&loc=d3e4845-128472 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 10 -Section 55 -Paragraph 37 -URI http://asc.fasb.org/extlink&oid=35744172&loc=d3e2207-128464 + Details
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- Definition Amount recognized as of the acquisition date for the identifiable assets acquired in excess of (less than) the aggregate liabilities assumed. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=39739317&loc=d3e4845-128472 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 10 -Section 55 -Paragraph 37 -URI http://asc.fasb.org/extlink&oid=35744172&loc=d3e2207-128464 + Details
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- Definition Amount of long-term debt due after one year or the normal operating cycle, if longer, assumed at the acquisition date. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=39739317&loc=d3e4845-128472 + Details
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- Definition Amount of other liabilities due after one year or the normal operating cycle, if longer, assumed at the acquisition date. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=39739317&loc=d3e4845-128472 + Details
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- Definition The amount of property, plant, and equipment recognized as of the acquisition date. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=39739317&loc=d3e4845-128472 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 10 -Section 55 -Paragraph 37 -URI http://asc.fasb.org/extlink&oid=35744172&loc=d3e2207-128464 + Details
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- Definition Percentage of voting equity interests acquired in a business combination achieved in stages, including equity interests in the acquiree held by the acquirer immediately before the acquisition date and acquired at the acquisition date. + References No definition available. + Details
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- Definition In a business combination achieved in stages, this element represents the amount of gain recognized by the entity as a result of remeasuring to fair value the equity interest in the acquiree it held before the business combination. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (g)(2) -URI http://asc.fasb.org/extlink&oid=25497992&loc=d3e1392-128463 + Details
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- Definition Amount of structure or a modification to a structure under construction. Includes recently completed structures or modifications to structures that have not been placed into service. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229 + Details
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- Definition Amount of long-term debt before deduction of unamortized discount or premium. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt, with initial maturities beyond one year or the normal operating cycle, if longer. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 20 -Article 5 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.22) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 22 -Article 5 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 16 -Article 9 + Details
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- Definition Amount of gain (loss), after tax expense or benefit and not previously recognized, resulting from the sale of a business component. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 205 -SubTopic 20 -Section 45 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=6892542&loc=d3e957-107759 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 205 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=6360339&loc=d3e1361-107760 + Details
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- Definition The gain (loss) resulting from the sale of a disposal group that is not a discontinued operation. It is included in income from continuing operations before income taxes in the income statement. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 205 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=6360339&loc=d3e1361-107760 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -SubTopic 10 -Section 45 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=8077374&loc=d3e2443-110228 + Details
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- Definition The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 260 -SubTopic 10 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 260 -SubTopic 10 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=7655603&loc=d3e1252-109256 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 260 -SubTopic 10 -Section 55 -Paragraph 52 -URI http://asc.fasb.org/extlink&oid=32703322&loc=d3e4984-109258 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 225 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03.21) -URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 225 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-04.19) -URI http://asc.fasb.org/extlink&oid=6879464&loc=d3e573970-122913 Reference 6: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 225 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-04.23) -URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882 Reference 7: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Paragraph 18 -Article 7 Reference 8: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 20 -Article 5 Reference 9: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Paragraph 21 -Article 9 + Details
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- Definition This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.12) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 323 -SubTopic 10 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=35755396&loc=d3e33749-111570 + Details
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- Definition The designation of funds furnished by a borrower to a lender to assure future payments of the borrower's real estate taxes and insurance obligations with respect to a mortgaged property. Escrow deposits may be made for a variety of other purposes such as earnest money and contingent payments. This element excludes replacement reserves which are an escrow separately provided for within the US GAAP taxonomy. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.10) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 + Details
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