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Estimated potential additional contribution obligation.

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Amount of contractual obligation, including, but not limited to, long-term debt, lease obligation, purchase obligation, and other commitments.

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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The book value of investments in real estate joint ventures including direct and indirect investments.

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COMMITMENTS AND CONTINGENCIES (Details) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022	Jul. 23, 2021
Loss Contingencies [Line Items]
Investment in real estate ventures	$ 589,195	$ 532,224
Drexel Square
Loss Contingencies [Line Items]
Contractual obligation	6,600
Estimated potential additional contribution obligation	2,200
3151 Market Street
Loss Contingencies [Line Items]
Construction loan amount	37,000
Investment in real estate ventures	316,900
One Uptown Venture
Loss Contingencies [Line Items]
Limited payment guarantee, percent of principle balance (up to)			25.00%
One Uptown Venture \| Carry Guarantee
Loss Contingencies [Line Items]
Limited payment guarantee, percent of principle balance (up to)			30.00%
Equity method investment, additional summarized financial information debt	10,000
Construction loan amount			$ 121,700
One Uptown Venture \| Payment Guarantee
Loss Contingencies [Line Items]
Limited payment guarantee, percent of principle balance (up to)			15.00%
Construction loan amount			$ 85,000
3025 JFK Venture
Loss Contingencies [Line Items]
Construction loan amount			$ 186,700
Unconsolidated Real Estate Ventures
Loss Contingencies [Line Items]
Unconsolidated real estate venture debt at 100%, gross	1,341,000
Equity method investment, additional summarized financial information debt	$ 12,700