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INVESTMENT IN UNCONSOLIDATED REAL ESTATE VENTURES - JGB Ventures (Details) | Dec. 31, 2020 property | May 29, 2015 a
--- | --- | ---
Schedule of Equity Method Investments [Line Items] |  |
Number of properties | property | 82 |
JBG 51 N 50 Patterson |  |
Schedule of Equity Method Investments [Line Items] |  |
Ownership percentage | 70.00% | 70.00%
Area owned by real estate venture of undeveloped parcels of land | a |  | 0.9
JBG 1250 First Street Office |  |
Schedule of Equity Method Investments [Line Items] |  |
Ownership percentage | 70.00% | 70.00%
Area owned by real estate venture of undeveloped parcels of land | a |  | 0.5
JBG Ventures |  |
Schedule of Equity Method Investments [Line Items] |  |
Number of properties | property | 2 |
JBG Ventures | JBG 51 N 50 Patterson |  |
Schedule of Equity Method Investments [Line Items] |  |
Ownership percentage |  | 30.00%
JBG Ventures | JBG 1250 First Street Office |  |
Schedule of Equity Method Investments [Line Items] |  |
Ownership percentage |  | 30.00%

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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. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 323 -SubTopic 10 -Section 50 -Paragraph 3 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=114001798&loc=d3e33918-111571 + Details
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