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Properties, Net (Details 4) ft² in Thousands |  |  | 6 Months Ended |
--- | --- | --- | --- | ---
Jun. 09, 2017 USD ($) ft² | Feb. 15, 2017 USD ($) ft² | Jun. 30, 2017 USD ($) ft² Property | Jul. 28, 2017 USD ($) ft² Property
Construction, Redevelopment and Dispositions |  |  |  |
Sale price of land | $ |  |  | $ 14,300,000 |
Gain on sale of land | $ |  |  | $ 4,200,000 |
Office properties under, or contractually committed for, construction or approved for redevelopment |  |  |  |
Construction, Redevelopment and Dispositions |  |  |  |
Square footage of real estate properties (in square feet) | ft² |  |  | 1,400 |
Number of real estate properties |  |  | 10 |
Newly constructed properties placed in service |  |  |  |
Construction, Redevelopment and Dispositions |  |  |  |
Number of real estate properties |  |  | 3 |
Square feet of properties placed in service | ft² |  |  | 295 |
Newly redeveloped properties placed in service |  |  |  |
Construction, Redevelopment and Dispositions |  |  |  |
Number of real estate properties |  |  | 3 |
Square feet of properties placed in service | ft² |  |  | 88 |
Partially operational properties |  |  |  |
Construction, Redevelopment and Dispositions |  |  |  |
Number of real estate properties |  |  | 2 |
Partially operational properties | Office properties under, or contractually committed for, construction or approved for redevelopment |  |  |  |
Construction, Redevelopment and Dispositions |  |  |  |
Number of real estate properties |  |  | 3 |
Properties under construction or contractually committed for construction |  |  |  |
Construction, Redevelopment and Dispositions |  |  |  |
Square footage of real estate properties (in square feet) | ft² |  |  | 1,300 |
Number of real estate properties |  |  | 8 |
Properties completed Held-for-future lease | Office properties under, or contractually committed for, construction or approved for redevelopment |  |  |  |
Construction, Redevelopment and Dispositions |  |  |  |
Number of real estate properties |  |  | 2 |
Properties under or approved for redevelopment |  |  |  |
Construction, Redevelopment and Dispositions |  |  |  |
Square footage of real estate properties (in square feet) | ft² |  |  | 61 |
Number of real estate properties |  |  | 2 |
Operating Properties | Regional Office | White Marsh, Maryland | Subsequent Event |  |  |  |
Construction, Redevelopment and Dispositions |  |  |  |
Square footage of real estate properties (in square feet) | ft² |  |  |  | 412
Transaction value | $ |  |  |  | $ 47,500,000
Number of real estate properties |  |  |  | 8
Operating Properties | Northern Virginia Defense/IT | Defense/Information Technology Locations | 3120 Fairview Park Drive |  |  |  |
Construction, Redevelopment and Dispositions |  |  |  |
Square footage of real estate properties (in square feet) | ft² |  | 190 |  |
Transaction value | $ |  | $ 39,000,000 |  |
Gain recognized | $ |  | $ 0 |  |
Operating Properties | Fort Meade/BW Corridor | Defense/Information Technology Locations | 1334 Ashton Road |  |  |  |
Construction, Redevelopment and Dispositions |  |  |  |
Square footage of real estate properties (in square feet) | ft² | 37 |  |  |
Transaction value | $ | $ 2,300,000 |  |  |
Gain recognized | $ | $ 0 |  |  |

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