Development Costs - Contemplated Debt Financing

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- Definition

Guarantee obligations maximum exposure cancelled.

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- Definition

Net gain (loss) on real estate venture transactions including real estate venture formation.

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No definition available.

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- Definition

The number of real estate properties sold during the period.

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Percentage of allocated gross sales value.

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- Definition

Sale of ownership interest percentage.

+ References

No definition available.

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- Definition

Amount of consideration received or receivable for the disposal of assets and liabilities, including discontinued operation.

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- Definition

Amount of the entity's equity method investment which has been sold.

+ References

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- Definition

The cash inflow associated with the sale of equity method investments, which are investments in joint ventures and entities in which the entity has an equity ownership interest normally of 20 to 50 percent and exercises significant influence.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 12
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3179-108585

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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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INVESTMENT IN UNCONSOLIDATED REAL ESTATE VENTURES - The Parc at Plymouth Meeting Venture (Details)		12 Months Ended
	Jan. 31, 2017 USD ($) housing_unit	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)
Schedule of Equity Method Investments [Line Items]
Proceeds from real estate venture sales		$ 9,730,000	$ 60,346,000	$ 145,416,000
Net gain on real estate venture transactions		$ 11,639,000	$ 142,233,000	$ 80,526,000
TB-BDN Plymouth Apartments
Schedule of Equity Method Investments [Line Items]
Sale of ownership interest percentage	50.00%
Gross sales price	$ 100,500,000
Allocated gross sales value of ownership interest, percentage	50.00%
Number of properties sold \| housing_unit	398
Guarantee obligations cancelled	$ 3,200,000
Proceeds from real estate venture sales	27,200,000
Net gain on real estate venture transactions	14,600,000
TB-BDN Plymouth Apartments \| Unconsolidated Real Estate Ventures
Schedule of Equity Method Investments [Line Items]
Equity in income (loss) of Real Estate Ventures	12,600,000
Pennsylvania \| TB-BDN Plymouth Apartments
Schedule of Equity Method Investments [Line Items]
Development costs contemplated debt financing	$ 54,000,000.0