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

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- Definition

Sale of ownership interest percentage.

+ References

No definition available.

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- Definition

Area of a real estate property.

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No definition available.

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- Definition

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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- 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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INVESTMENT IN UNCONSOLIDATED REAL ESTATE VENTURES - Four Tower Bridge Acquisition (Details) $ in Thousands		12 Months Ended
	Jan. 05, 2018 USD ($) ft²	Dec. 31, 2019 USD ($) ft²	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)
Schedule of Equity Method Investments [Line Items]
Area of real estate property \| ft²		16,711,387
Net gain on real estate venture transactions		$ 11,639	$ 142,233	$ 80,526
Four Tower Bridge
Schedule of Equity Method Investments [Line Items]
Ownership percentage	35.00%
Net gain on real estate venture transactions	$ 11,600
Seven Tower Bridge
Schedule of Equity Method Investments [Line Items]
Sale of ownership interest percentage	20.00%
Pennsylvania \| Conshohocken \| Four Tower Bridge
Schedule of Equity Method Investments [Line Items]
Area of real estate property \| ft²	86,021
Real estate property debt	$ 9,700