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Real Estate and Accumulated Depreciation Schedule of Real Estate and Accumulated Depreciation (Details) - USD ($) $ in Thousands | 12 Months Ended |
--- | --- | ---
Dec. 31, 2018 | Dec. 31, 2017
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |
Encumbrances | [1] | $ 2,964,572 |
Original Land |  | 4,959,995 |
Original Building |  | 12,763,317 |
Costs Capitalized Subsequent to Acquisition |  | 3,882,233 |
Land and improvements |  | 5,072,568 |
Buildings and Improvements |  | 15,753,683 |
Land Held for Development | [2] | 200,498 |
Development and Construction in Progress |  | 578,796 |
Total |  | 21,605,545 |
Accumulated Depreciation |  | 4,871,102 |
Furniture, fixtures and equipment |  | 44,351 | $ 37,928
Furniture, fixtures and equipment accumulated depreciation |  | 26,675 |
Real Estate Aggregate Cost For Tax Purposes |  | 17,900,000 |
Real Estate Aggregate Accumulated Depreciation For Tax Purposes |  | $ 3,900,000 |
Real Estate and Accumulated Depreciation, Life Used for Depreciation |  | 40 years |
Unamortized deferred finance costs |  | $ (30,756) |
767 Fifth Avenue (the General Motors Building) |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |
Property Name |  | 767 Fifth Avenue (the General Motors Building) |
Type |  | Office |
Location |  | New York, NY |
Encumbrances |  | $ 2,270,534 |
Original Land |  | 1,796,252 |
Original Building |  | 1,532,654 |
Costs Capitalized Subsequent to Acquisition |  | 189,657 |
Land and improvements |  | 1,796,252 |
Buildings and Improvements |  | 1,722,311 |
Land Held for Development |  | 0 |
Development and Construction in Progress |  | 0 |
Total |  | 3,518,563 |
Accumulated Depreciation |  | $ 271,534 |
Year(s) Built / Renovated |  | 1968 |
Year(s) Acquired |  | 2013 |
Depreciable Lives (Years) | [3] | -1 |
Prudential Center |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |
Property Name |  | Prudential Center |
Type |  | Office |
Location |  | Boston, MA |
Encumbrances |  | $ 0 |
Original Land |  | 92,077 |
Original Building |  | 948,357 |
Costs Capitalized Subsequent to Acquisition |  | 532,802 |
Land and improvements |  | 115,638 |
Buildings and Improvements |  | 1,457,494 |
Land Held for Development |  | 104 |
Development and Construction in Progress |  | 0 |
Total |  | 1,573,236 |
Accumulated Depreciation |  | $ 550,109 |
Year(s) Built / Renovated |  | 1965/1993/2002/2016-2017 |
Year(s) Acquired |  | 1998/1999/2000 |
Depreciable Lives (Years) | [3] | -1 |
Embarcadero Center |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |
Property Name |  | Embarcadero Center |
Type |  | Office |
Location |  | San Francisco, CA |
Encumbrances |  | $ 0 |
Original Land |  | 179,697 |
Original Building |  | 847,410 |
Costs Capitalized Subsequent to Acquisition |  | 368,967 |
Land and improvements |  | 195,987 |
Buildings and Improvements |  | 1,200,087 |
Land Held for Development |  | 0 |
Development and Construction in Progress |  | 0 |
Total |  | 1,396,074 |
Accumulated Depreciation |  | $ 612,981 |
Year(s) Built / Renovated |  | 1970/1989 |
Year(s) Acquired |  | 1998-1999 |
Depreciable Lives (Years) | [3] | -1 |
399 Park Avenue |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |
Property Name |  | 399 Park Avenue |
Type |  | Office |
Location |  | New York, NY |
Encumbrances |  | $ 0 |
Original Land |  | 339,200 |
Original Building |  | 700,358 |
Costs Capitalized Subsequent to Acquisition |  | 247,092 |
Land and improvements |  | 354,107 |
Buildings and Improvements |  | 932,543 |
Land Held for Development |  | 0 |
Development and Construction in Progress |  | 0 |
Total |  | 1,286,650 |
Accumulated Depreciation |  | $ 332,911 |
Year(s) Built / Renovated |  | 1961/2018 |
Year(s) Acquired |  | 2002 |
Depreciable Lives (Years) | [3] | -1 |
Salesforce Tower |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |
Property Name |  | Salesforce Tower |
Type |  | Office |
Location |  | San Francisco, CA |
Encumbrances |  | $ 0 |
Original Land |  | 200,349 |
Original Building |  | 919,565 |
Costs Capitalized Subsequent to Acquisition |  | 0 |
Land and improvements |  | 200,349 |
Buildings and Improvements |  | 919,565 |
Land Held for Development |  | 0 |
Development and Construction in Progress |  | 0 |
Total |  | 1,119,914 |
Accumulated Depreciation |  | $ 9,509 |
Year(s) Built / Renovated |  | 2018 |
Year(s) Acquired |  | 2013 |
Depreciable Lives (Years) | [3] | -1 |
601 Lexington Avenue |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |
Property Name |  | 601 Lexington Avenue |
Type |  | Office |
Location |  | New York, NY |
Encumbrances |  | $ 658,792 |
Original Land |  | 241,600 |
Original Building |  | 494,782 |
Costs Capitalized Subsequent to Acquisition |  | 361,985 |
Land and improvements |  | 289,639 |
Buildings and Improvements |  | 637,044 |
Land Held for Development |  | 0 |
Development and Construction in Progress |  | 171,684 |
Total |  | 1,098,367 |
Accumulated Depreciation |  | $ 272,936 |
Year(s) Built / Renovated |  | 1977/1997 |
Year(s) Acquired |  | 2001 |
Depreciable Lives (Years) | [3] | -1 |
200 Clarendon Street and Garage |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |
Property Name |  | 200 Clarendon Street and Garage |
Type |  | Office |
Location |  | Boston, MA |
Encumbrances |  | $ 0 |
Original Land |  | 219,543 |
Original Building |  | 667,884 |
Costs Capitalized Subsequent to Acquisition |  | 164,073 |
Land and improvements |  | 219,616 |
Buildings and Improvements |  | 822,218 |
Land Held for Development |  | 9,666 |
Development and Construction in Progress |  | 0 |
Total |  | 1,051,500 |
Accumulated Depreciation |  | $ 192,137 |
Year(s) Built / Renovated |  | 1976 |
Year(s) Acquired |  | 2010 |
Depreciable Lives (Years) | [3] | -1 |
250 West 55th Street |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |
Property Name |  | 250 West 55th Street |
Type |  | Office |
Location |  | New York, NY |
Encumbrances |  | $ 0 |
Original Land |  | 285,263 |
Original Building |  | 603,167 |
Costs Capitalized Subsequent to Acquisition |  | 48,642 |
Land and improvements |  | 285,263 |
Buildings and Improvements |  | 651,809 |
Land Held for Development |  | 0 |
Development and Construction in Progress |  | 0 |
Total |  | 937,072 |
Accumulated Depreciation |  | $ 94,434 |
Year(s) Built / Renovated |  | 2014 |
Year(s) Acquired |  | 2007 |
Depreciable Lives (Years) | [3] | -1 |
100 Federal Street |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |
Property Name |  | 100 Federal Street |
Type |  | Office |
Location |  | Boston, MA |
Encumbrances |  | $ 0 |
Original Land |  | 131,067 |
Original Building |  | 435,954 |
Costs Capitalized Subsequent to Acquisition |  | 99,702 |
Land and improvements |  | 131,067 |
Buildings and Improvements |  | 535,656 |
Land Held for Development |  | 0 |
Development and Construction in Progress |  | 0 |
Total |  | 666,723 |
Accumulated Depreciation |  | $ 105,536 |
Year(s) Built / Renovated |  | 1971-1975/2017 |
Year(s) Acquired |  | 2012 |
Depreciable Lives (Years) | [3] | -1 |
Carnegie Center |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |
Property Name |  | Carnegie Center |
Type |  | Office |
Location |  | Princeton, NJ |
Encumbrances |  | $ 0 |
Original Land |  | 107,997 |
Original Building |  | 389,359 |
Costs Capitalized Subsequent to Acquisition |  | 158,752 |
Land and improvements |  | 108,948 |
Buildings and Improvements |  | 543,974 |
Land Held for Development |  | 3,186 |
Development and Construction in Progress |  | 0 |
Total |  | 656,108 |
Accumulated Depreciation |  | $ 241,570 |
Year(s) Built / Renovated |  | 1983-2016 |
Year(s) Acquired |  | 1998/1999/2000/2007/2014/2017 |
Depreciable Lives (Years) | [3] | -1 |
Times Square Tower |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |
Property Name |  | Times Square Tower |
Type |  | Office |
Location |  | New York, NY |
Encumbrances |  | $ 0 |
Original Land |  | 165,413 |
Original Building |  | 380,438 |
Costs Capitalized Subsequent to Acquisition |  | 94,451 |
Land and improvements |  | 169,193 |
Buildings and Improvements |  | 471,109 |
Land Held for Development |  | 0 |
Development and Construction in Progress |  | 0 |
Total |  | 640,302 |
Accumulated Depreciation |  | $ 206,067 |
Year(s) Built / Renovated |  | 2004 |
Year(s) Acquired |  | 2000 |
Depreciable Lives (Years) | [3] | -1 |
Atlantic Wharf |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |
Property Name |  | Atlantic Wharf |
Type |  | Office |
Location |  | Boston, MA |
Encumbrances |  | $ 0 |
Original Land |  | 63,988 |
Original Building |  | 454,537 |
Costs Capitalized Subsequent to Acquisition |  | 17,184 |
Land and improvements |  | 63,988 |
Buildings and Improvements |  | 471,721 |
Land Held for Development |  | 0 |
Development and Construction in Progress |  | 0 |
Total |  | 535,709 |
Accumulated Depreciation |  | $ 116,238 |
Year(s) Built / Renovated |  | 2011 |
Year(s) Acquired |  | 2007 |
Depreciable Lives (Years) | [3] | -1 |
510 Madison Avenue |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |
Property Name |  | 510 Madison Avenue |
Type |  | Office |
Location |  | New York, NY |
Encumbrances |  | $ 0 |
Original Land |  | 103,000 |
Original Building |  | 253,665 |
Costs Capitalized Subsequent to Acquisition |  | 24,992 |
Land and improvements |  | 103,000 |
Buildings and Improvements |  | 278,657 |
Land Held for Development |  | 0 |
Development and Construction in Progress |  | 0 |
Total |  | 381,657 |
Accumulated Depreciation |  | $ 62,507 |
Year(s) Built / Renovated |  | 2012 |
Year(s) Acquired |  | 2010 |
Depreciable Lives (Years) | [3] | -1 |
Fountain Square |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |
Property Name |  | Fountain Square |
Type |  | Office |
Location |  | Reston, VA |
Encumbrances |  | $ 0 |
Original Land |  | 56,853 |
Original Building |  | 306,298 |
Costs Capitalized Subsequent to Acquisition |  | 3,170 |
Land and improvements |  | 56,853 |
Buildings and Improvements |  | 309,468 |
Land Held for Development |  | 0 |
Development and Construction in Progress |  | 0 |
Total |  | 366,321 |
Accumulated Depreciation |  | $ 68,390 |
Year(s) Built / Renovated |  | 1986-1990 |
Year(s) Acquired |  | 2012 |
Depreciable Lives (Years) | [3] | -1 |
599 Lexington Avenue |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |
Property Name |  | 599 Lexington Avenue |
Type |  | Office |
Location |  | New York, NY |
Encumbrances |  | $ 0 |
Original Land |  | 81,040 |
Original Building |  | 100,507 |
Costs Capitalized Subsequent to Acquisition |  | 174,213 |
Land and improvements |  | 87,852 |
Buildings and Improvements |  | 267,908 |
Land Held for Development |  | 0 |
Development and Construction in Progress |  | 0 |
Total |  | 355,760 |
Accumulated Depreciation |  | $ 170,678 |
Year(s) Built / Renovated |  | 1986 |
Year(s) Acquired |  | 1997 |
Depreciable Lives (Years) | [3] | -1 |
680 Folsom Street |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |
Property Name |  | 680 Folsom Street |
Type |  | Office |
Location |  | San Francisco, CA |
Encumbrances |  | $ 0 |
Original Land |  | 72,545 |
Original Building |  | 219,766 |
Costs Capitalized Subsequent to Acquisition |  | 7,829 |
Land and improvements |  | 72,545 |
Buildings and Improvements |  | 227,595 |
Land Held for Development |  | 0 |
Development and Construction in Progress |  | 0 |
Total |  | 300,140 |
Accumulated Depreciation |  | $ 38,230 |
Year(s) Built / Renovated |  | 2014 |
Year(s) Acquired |  | 2012 |
Depreciable Lives (Years) | [3] | -1 |
601 Massachusetts Avenue |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |
Property Name |  | 601 Massachusetts Avenue |
Type |  | Office |
Location |  | Washington, DC |
Encumbrances |  | $ 0 |
Original Land |  | 95,310 |
Original Building |  | 165,173 |
Costs Capitalized Subsequent to Acquisition |  | 3,900 |
Land and improvements |  | 95,322 |
Buildings and Improvements |  | 169,061 |
Land Held for Development |  | 0 |
Development and Construction in Progress |  | 0 |
Total |  | 264,383 |
Accumulated Depreciation |  | $ 18,263 |
Year(s) Built / Renovated |  | 2016 |
Year(s) Acquired |  | 2008 |
Depreciable Lives (Years) | [3] | -1 |
South of Market and Democracy Tower |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |
Property Name |  | South of Market and Democracy Tower |
Type |  | Office |
Location |  | Reston, VA |
Encumbrances |  | $ 0 |
Original Land |  | 13,603 |
Original Building |  | 237,479 |
Costs Capitalized Subsequent to Acquisition |  | 12,428 |
Land and improvements |  | 13,687 |
Buildings and Improvements |  | 249,823 |
Land Held for Development |  | 0 |
Development and Construction in Progress |  | 0 |
Total |  | 263,510 |
Accumulated Depreciation |  | $ 91,072 |
Year(s) Built / Renovated |  | 2008-2009 |
Year(s) Acquired |  | 2003 |
Depreciable Lives (Years) | [3] | -1 |
Bay Colony Corporate Center |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |
Property Name |  | Bay Colony Corporate Center |
Type |  | Office |
Location |  | Waltham, MA |
Encumbrances |  | $ 0 |
Original Land |  | 18,789 |
Original Building |  | 148,451 |
Costs Capitalized Subsequent to Acquisition |  | 77,133 |
Land and improvements |  | 18,789 |
Buildings and Improvements |  | 225,584 |
Land Held for Development |  | 0 |
Development and Construction in Progress |  | 0 |
Total |  | 244,373 |
Accumulated Depreciation |  | $ 68,903 |
Year(s) Built / Renovated |  | 1985-1989 |
Year(s) Acquired |  | 2011 |
Depreciable Lives (Years) | [3] | -1 |
Gateway Center |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |
Property Name |  | Gateway Center |
Type |  | Office |
Location |  | San Francisco, CA |
Encumbrances |  | $ 0 |
Original Land |  | 28,255 |
Original Building |  | 139,245 |
Costs Capitalized Subsequent to Acquisition |  | 64,831 |
Land and improvements |  | 30,627 |
Buildings and Improvements |  | 201,704 |
Land Held for Development |  | 0 |
Development and Construction in Progress |  | 0 |
Total |  | 232,331 |
Accumulated Depreciation |  | $ 107,640 |
Year(s) Built / Renovated |  | 1984/1986/2002 |
Year(s) Acquired |  | 1999 |
Depreciable Lives (Years) | [3] | -1 |
535 Mission Street |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |
Property Name |  | 535 Mission Street |
Type |  | Office |
Location |  | San Francisco, CA |
Encumbrances |  | $ 0 |
Original Land |  | 40,933 |
Original Building |  | 148,378 |
Costs Capitalized Subsequent to Acquisition |  | 3,259 |
Land and improvements |  | 40,933 |
Buildings and Improvements |  | 151,637 |
Land Held for Development |  | 0 |
Development and Construction in Progress |  | 0 |
Total |  | 192,570 |
Accumulated Depreciation |  | $ 20,576 |
Year(s) Built / Renovated |  | 2015 |
Year(s) Acquired |  | 2013 |
Depreciable Lives (Years) | [3] | -1 |
2200 Pennsylvania Avenue |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |
Property Name |  | 2200 Pennsylvania Avenue |
Type |  | Office |
Location |  | Washington, DC |
Encumbrances |  | $ 0 |
Original Land |  | 0 |
Original Building |  | 183,541 |
Costs Capitalized Subsequent to Acquisition |  | 4,535 |
Land and improvements |  | 0 |
Buildings and Improvements |  | 188,076 |
Land Held for Development |  | 0 |
Development and Construction in Progress |  | 0 |
Total |  | 188,076 |
Accumulated Depreciation |  | $ 52,280 |
Year(s) Built / Renovated |  | 2011 |
Year(s) Acquired |  | 2008 |
Depreciable Lives (Years) | [3] | -1 |
Mountain View Research Park |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |
Property Name |  | Mountain View Research Park |
Type |  | Office |
Location |  | Mountain View, CA |
Encumbrances |  | $ 0 |
Original Land |  | 95,066 |
Original Building |  | 68,373 |
Costs Capitalized Subsequent to Acquisition |  | 9,988 |
Land and improvements |  | 95,066 |
Buildings and Improvements |  | 78,361 |
Land Held for Development |  | 0 |
Development and Construction in Progress |  | 0 |
Total |  | 173,427 |
Accumulated Depreciation |  | $ 17,866 |
Year(s) Built / Renovated |  | 1977-1981/2007-2013 |
Year(s) Acquired |  | 2013 |
Depreciable Lives (Years) | [3] | -1 |
Reservoir Place |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |
Property Name |  | Reservoir Place |
Type |  | Office |
Location |  | Waltham, MA |
Encumbrances |  | $ 0 |
Original Land |  | 18,605 |
Original Building |  | 104,124 |
Costs Capitalized Subsequent to Acquisition |  | 45,144 |
Land and improvements |  | 20,108 |
Buildings and Improvements |  | 147,765 |
Land Held for Development |  | 0 |
Development and Construction in Progress |  | 0 |
Total |  | 167,873 |
Accumulated Depreciation |  | $ 64,683 |
Year(s) Built / Renovated |  | 1955/1987/2017 |
Year(s) Acquired |  | 1997/1998 |
Depreciable Lives (Years) | [3] | -1 |
1330 Connecticut Avenue |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |
Property Name |  | 1330 Connecticut Avenue |
Type |  | Office |
Location |  | Washington, DC |
Encumbrances |  | $ 0 |
Original Land |  | 25,982 |
Original Building |  | 82,311 |
Costs Capitalized Subsequent to Acquisition |  | 36,089 |
Land and improvements |  | 27,135 |
Buildings and Improvements |  | 117,247 |
Land Held for Development |  | 0 |
Development and Construction in Progress |  | 0 |
Total |  | 144,382 |
Accumulated Depreciation |  | $ 27,535 |
Year(s) Built / Renovated |  | 1984/2018 |
Year(s) Acquired |  | 2004 |
Depreciable Lives (Years) | [3] | -1 |
Kingstowne Towne Center |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |
Property Name |  | Kingstowne Towne Center |
Type |  | Office |
Location |  | Alexandria, VA |
Encumbrances |  | $ 0 |
Original Land |  | 18,021 |
Original Building |  | 109,038 |
Costs Capitalized Subsequent to Acquisition |  | 2,098 |
Land and improvements |  | 18,062 |
Buildings and Improvements |  | 111,095 |
Land Held for Development |  | 0 |
Development and Construction in Progress |  | 0 |
Total |  | 129,157 |
Accumulated Depreciation |  | $ 41,469 |
Year(s) Built / Renovated |  | 2003-2006 |
Year(s) Acquired |  | 2007 |
Depreciable Lives (Years) | [3] | -1 |
One Freedom Square |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |
Property Name |  | One Freedom Square |
Type |  | Office |
Location |  | Reston, VA |
Encumbrances |  | $ 0 |
Original Land |  | 9,929 |
Original Building |  | 84,504 |
Costs Capitalized Subsequent to Acquisition |  | 32,256 |
Land and improvements |  | 11,293 |
Buildings and Improvements |  | 115,396 |
Land Held for Development |  | 0 |
Development and Construction in Progress |  | 0 |
Total |  | 126,689 |
Accumulated Depreciation |  | $ 54,652 |
Year(s) Built / Renovated |  | 2000 |
Year(s) Acquired |  | 2003 |
Depreciable Lives (Years) | [3] | -1 |
Capital Gallery |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |
Property Name |  | Capital Gallery |
Type |  | Office |
Location |  | Washington, DC |
Encumbrances |  | $ 0 |
Original Land |  | 4,725 |
Original Building |  | 29,565 |
Costs Capitalized Subsequent to Acquisition |  | 87,231 |
Land and improvements |  | 8,662 |
Buildings and Improvements |  | 112,859 |
Land Held for Development |  | 0 |
Development and Construction in Progress |  | 0 |
Total |  | 121,521 |
Accumulated Depreciation |  | $ 67,759 |
Year(s) Built / Renovated |  | 1981/2006 |
Year(s) Acquired |  | 2007 |
Depreciable Lives (Years) | [3] | -1 |
Weston Corporate Center |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |
Property Name |  | Weston Corporate Center |
Type |  | Office |
Location |  | Weston, MA |
Encumbrances |  | $ 0 |
Original Land |  | 25,753 |
Original Building |  | 92,312 |
Costs Capitalized Subsequent to Acquisition |  | (123) |
Land and improvements |  | 25,854 |
Buildings and Improvements |  | 92,088 |
Land Held for Development |  | 0 |
Development and Construction in Progress |  | 0 |
Total |  | 117,942 |
Accumulated Depreciation |  | $ 26,176 |
Year(s) Built / Renovated |  | 2010 |
Year(s) Acquired |  | 2001 |
Depreciable Lives (Years) | [3] | -1 |
Two Freedom Square |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |
Property Name |  | Two Freedom Square |
Type |  | Office |
Location |  | Reston, VA |
Encumbrances |  | $ 0 |
Original Land |  | 13,930 |
Original Building |  | 77,739 |
Costs Capitalized Subsequent to Acquisition |  | 23,427 |
Land and improvements |  | 15,420 |
Buildings and Improvements |  | 99,676 |
Land Held for Development |  | 0 |
Development and Construction in Progress |  | 0 |
Total |  | 115,096 |
Accumulated Depreciation |  | $ 51,291 |
Year(s) Built / Renovated |  | 2001 |
Year(s) Acquired |  | 2003 |
Depreciable Lives (Years) | [3] | -1 |
One and Two Reston Overlook |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |
Property Name |  | One and Two Reston Overlook |
Type |  | Office |
Location |  | Reston, VA |
Encumbrances |  | $ 0 |
Original Land |  | 16,456 |
Original Building |  | 66,192 |
Costs Capitalized Subsequent to Acquisition |  | 24,181 |
Land and improvements |  | 16,179 |
Buildings and Improvements |  | 90,650 |
Land Held for Development |  | 0 |
Development and Construction in Progress |  | 0 |
Total |  | 106,829 |
Accumulated Depreciation |  | $ 47,668 |
Year(s) Built / Renovated |  | 1999 |
Year(s) Acquired |  | 2000 |
Depreciable Lives (Years) | [3] | -1 |
140 Kendrick Street |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |
Property Name |  | 140 Kendrick Street |
Type |  | Office |
Location |  | Needham, MA |
Encumbrances |  | $ 0 |
Original Land |  | 18,095 |
Original Building |  | 66,905 |
Costs Capitalized Subsequent to Acquisition |  | 17,553 |
Land and improvements |  | 19,092 |
Buildings and Improvements |  | 83,461 |
Land Held for Development |  | 0 |
Development and Construction in Progress |  | 0 |
Total |  | 102,553 |
Accumulated Depreciation |  | $ 32,360 |
Year(s) Built / Renovated |  | 2000 |
Year(s) Acquired |  | 2004 |
Depreciable Lives (Years) | [3] | -1 |
Discovery Square |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |
Property Name |  | Discovery Square |
Type |  | Office |
Location |  | Reston, VA |
Encumbrances |  | $ 0 |
Original Land |  | 11,198 |
Original Building |  | 71,782 |
Costs Capitalized Subsequent to Acquisition |  | 17,753 |
Land and improvements |  | 12,533 |
Buildings and Improvements |  | 88,200 |
Land Held for Development |  | 0 |
Development and Construction in Progress |  | 0 |
Total |  | 100,733 |
Accumulated Depreciation |  | $ 39,574 |
Year(s) Built / Renovated |  | 2001 |
Year(s) Acquired |  | 2003 |
Depreciable Lives (Years) | [3] | -1 |
355 Main Street |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |
Property Name |  | 355 Main Street |
Type |  | Office |
Location |  | Cambridge, MA |
Encumbrances |  | $ 0 |
Original Land |  | 18,863 |
Original Building |  | 53,346 |
Costs Capitalized Subsequent to Acquisition |  | 23,701 |
Land and improvements |  | 21,173 |
Buildings and Improvements |  | 74,737 |
Land Held for Development |  | 0 |
Development and Construction in Progress |  | 0 |
Total |  | 95,910 |
Accumulated Depreciation |  | $ 23,691 |
Year(s) Built / Renovated |  | 1981/1996/2013 |
Year(s) Acquired |  | 2006 |
Depreciable Lives (Years) | [3] | -1 |
10 CityPoint |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |
Property Name |  | 10 CityPoint |
Type |  | Office |
Location |  | Waltham, MA |
Encumbrances |  | $ 0 |
Original Land |  | 1,953 |
Original Building |  | 85,752 |
Costs Capitalized Subsequent to Acquisition |  | 4,515 |
Land and improvements |  | 2,116 |
Buildings and Improvements |  | 90,104 |
Land Held for Development |  | 0 |
Development and Construction in Progress |  | 0 |
Total |  | 92,220 |
Accumulated Depreciation |  | $ 7,772 |
Year(s) Built / Renovated |  | 2016 |
Year(s) Acquired |  | 1997 |
Depreciable Lives (Years) | [3] | -1 |
90 Broadway |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |
Property Name |  | 90 Broadway |
Type |  | Office |
Location |  | Cambridge, MA |
Encumbrances |  | $ 0 |
Original Land |  | 19,104 |
Original Building |  | 52,078 |
Costs Capitalized Subsequent to Acquisition |  | 18,363 |
Land and improvements |  | 20,785 |
Buildings and Improvements |  | 68,760 |
Land Held for Development |  | 0 |
Development and Construction in Progress |  | 0 |
Total |  | 89,545 |
Accumulated Depreciation |  | $ 21,302 |
Year(s) Built / Renovated |  | 1983/1998/2013 |
Year(s) Acquired |  | 2006 |
Depreciable Lives (Years) | [3] | -1 |
230 CityPoint |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |
Property Name |  | 230 CityPoint |
Type |  | Office |
Location |  | Waltham, MA |
Encumbrances |  | $ 0 |
Original Land |  | 13,189 |
Original Building |  | 49,823 |
Costs Capitalized Subsequent to Acquisition |  | 21,914 |
Land and improvements |  | 13,593 |
Buildings and Improvements |  | 71,333 |
Land Held for Development |  | 0 |
Development and Construction in Progress |  | 0 |
Total |  | 84,926 |
Accumulated Depreciation |  | $ 26,357 |
Year(s) Built / Renovated |  | 1992 |
Year(s) Acquired |  | 2005 |
Depreciable Lives (Years) | [3] | -1 |
Waltham Weston Corporate Center |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |
Property Name |  | Waltham Weston Corporate Center |
Type |  | Office |
Location |  | Waltham, MA |
Encumbrances |  | $ 0 |
Original Land |  | 10,385 |
Original Building |  | 60,694 |
Costs Capitalized Subsequent to Acquisition |  | 11,449 |
Land and improvements |  | 11,097 |
Buildings and Improvements |  | 71,431 |
Land Held for Development |  | 0 |
Development and Construction in Progress |  | 0 |
Total |  | 82,528 |
Accumulated Depreciation |  | $ 32,739 |
Year(s) Built / Renovated |  | 2003 |
Year(s) Acquired |  | 1999 |
Depreciable Lives (Years) | [3] | -1 |
77 CityPoint |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |
Property Name |  | 77 CityPoint |
Type |  | Office |
Location |  | Waltham, MA |
Encumbrances |  | $ 0 |
Original Land |  | 13,847 |
Original Building |  | 60,383 |
Costs Capitalized Subsequent to Acquisition |  | 5,858 |
Land and improvements |  | 13,873 |
Buildings and Improvements |  | 66,215 |
Land Held for Development |  | 0 |
Development and Construction in Progress |  | 0 |
Total |  | 80,088 |
Accumulated Depreciation |  | $ 25,107 |
Year(s) Built / Renovated |  | 2008 |
Year(s) Acquired |  | 2001 |
Depreciable Lives (Years) | [3] | -1 |
3625-3635 Peterson Way |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |
Property Name |  | 3625-3635 Peterson Way |
Type |  | Office |
Location |  | Santa Clara, CA |
Encumbrances |  | $ 0 |
Original Land |  | 63,206 |
Original Building |  | 14,879 |
Costs Capitalized Subsequent to Acquisition |  | 673 |
Land and improvements |  | 63,206 |
Buildings and Improvements |  | 14,879 |
Land Held for Development |  | 673 |
Development and Construction in Progress |  | 0 |
Total |  | 78,758 |
Accumulated Depreciation |  | $ 8,146 |
Year(s) Built / Renovated |  | 1979 |
Year(s) Acquired |  | 2016 |
Depreciable Lives (Years) | [3] | -1 |
2440 West El Camino Real |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |
Property Name |  | 2440 West El Camino Real |
Type |  | Office |
Location |  | Mountain View, CA |
Encumbrances |  | $ 0 |
Original Land |  | 16,741 |
Original Building |  | 51,285 |
Costs Capitalized Subsequent to Acquisition |  | 3,411 |
Land and improvements |  | 16,741 |
Buildings and Improvements |  | 54,696 |
Land Held for Development |  | 0 |
Development and Construction in Progress |  | 0 |
Total |  | 71,437 |
Accumulated Depreciation |  | $ 12,562 |
Year(s) Built / Renovated |  | 1987/2003 |
Year(s) Acquired |  | 2011 |
Depreciable Lives (Years) | [3] | -1 |
300 Binney Street |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |
Property Name |  | 300 Binney Street |
Type |  | Office |
Location |  | Cambridge, MA |
Encumbrances |  | $ 0 |
Original Land |  | 18,080 |
Original Building |  | 51,262 |
Costs Capitalized Subsequent to Acquisition |  | 140 |
Land and improvements |  | 18,080 |
Buildings and Improvements |  | 51,402 |
Land Held for Development |  | 0 |
Development and Construction in Progress |  | 0 |
Total |  | 69,482 |
Accumulated Depreciation |  | $ 9,450 |
Year(s) Built / Renovated |  | 2013 |
Year(s) Acquired |  | 2009 |
Depreciable Lives (Years) | [3] | (1) |
191 Spring Street |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |
Property Name |  | 191 Spring Street |
Type |  | Office |
Location |  | Lexington, MA |
Encumbrances |  | $ 0 |
Original Land |  | 2,850 |
Original Building |  | 59,751 |
Costs Capitalized Subsequent to Acquisition |  | 6,235 |
Land and improvements |  | 3,151 |
Buildings and Improvements |  | 65,685 |
Land Held for Development |  | 0 |
Development and Construction in Progress |  | 0 |
Total |  | 68,836 |
Accumulated Depreciation |  | $ 19,543 |
Year(s) Built / Renovated |  | 1971/1995/2018 |
Year(s) Acquired |  | 1997 |
Depreciable Lives (Years) | [3] | (1) |
Wisconsin Place |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |
Property Name |  | Wisconsin Place |
Type |  | Office |
Location |  | Chevy Chase, MD |
Encumbrances |  | $ 0 |
Original Land |  | 0 |
Original Building |  | 53,349 |
Costs Capitalized Subsequent to Acquisition |  | 14,889 |
Land and improvements |  | 0 |
Buildings and Improvements |  | 68,238 |
Land Held for Development |  | 0 |
Development and Construction in Progress |  | 0 |
Total |  | 68,238 |
Accumulated Depreciation |  | $ 22,936 |
Year(s) Built / Renovated |  | 2009 |
Year(s) Acquired |  | 2004 |
Depreciable Lives (Years) | [3] | -1 |
Reston Corporate Center |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |
Property Name |  | Reston Corporate Center |
Type |  | Office |
Location |  | Reston, VA |
Encumbrances |  | $ 0 |
Original Land |  | 9,135 |
Original Building |  | 50,857 |
Costs Capitalized Subsequent to Acquisition |  | 6,236 |
Land and improvements |  | 10,148 |
Buildings and Improvements |  | 56,080 |
Land Held for Development |  | 0 |
Development and Construction in Progress |  | 0 |
Total |  | 66,228 |
Accumulated Depreciation |  | $ 28,315 |
Year(s) Built / Renovated |  | 1984 |
Year(s) Acquired |  | 1998 |
Depreciable Lives (Years) | [3] | -1 |
New Dominion Technology Park, Bldg. Two |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |
Property Name |  | New Dominion Technology Park, Bldg. Two |
Type |  | Office |
Location |  | Herndon, VA |
Encumbrances |  | $ 0 |
Original Land |  | 5,584 |
Original Building |  | 51,868 |
Costs Capitalized Subsequent to Acquisition |  | 4,157 |
Land and improvements |  | 6,510 |
Buildings and Improvements |  | 55,099 |
Land Held for Development |  | 0 |
Development and Construction in Progress |  | 0 |
Total |  | 61,609 |
Accumulated Depreciation |  | $ 25,421 |
Year(s) Built / Renovated |  | 2004 |
Year(s) Acquired |  | 1998 |
Depreciable Lives (Years) | [3] | -1 |
255 Main Street |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |
Property Name |  | 255 Main Street |
Type |  | Office |
Location |  | Cambridge, MA |
Encumbrances |  | $ 0 |
Original Land |  | 134 |
Original Building |  | 25,110 |
Costs Capitalized Subsequent to Acquisition |  | 29,672 |
Land and improvements |  | 548 |
Buildings and Improvements |  | 54,368 |
Land Held for Development |  | 0 |
Development and Construction in Progress |  | 0 |
Total |  | 54,916 |
Accumulated Depreciation |  | $ 30,180 |
Year(s) Built / Renovated |  | 1987 |
Year(s) Acquired |  | 1997 |
Depreciable Lives (Years) | [3] | -1 |
200 West Street |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |
Property Name |  | 200 West Street |
Type |  | Office |
Location |  | Waltham, MA |
Encumbrances |  | $ 0 |
Original Land |  | 16,148 |
Original Building |  | 24,983 |
Costs Capitalized Subsequent to Acquisition |  | 11,120 |
Land and improvements |  | 16,813 |
Buildings and Improvements |  | 35,438 |
Land Held for Development |  | 0 |
Development and Construction in Progress |  | 0 |
Total |  | 52,251 |
Accumulated Depreciation |  | $ 22,544 |
Year(s) Built / Renovated |  | 1999 |
Year(s) Acquired |  | 1997 |
Depreciable Lives (Years) | [3] | -1 |
New Dominion Technology Park, Bldg. One |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |
Property Name |  | New Dominion Technology Park, Bldg. One |
Type |  | Office |
Location |  | Herndon, VA |
Encumbrances |  | $ 29,675 |
Original Land |  | 3,880 |
Original Building |  | 43,227 |
Costs Capitalized Subsequent to Acquisition |  | 3,927 |
Land and improvements |  | 4,583 |
Buildings and Improvements |  | 46,451 |
Land Held for Development |  | 0 |
Development and Construction in Progress |  | 0 |
Total |  | 51,034 |
Accumulated Depreciation |  | $ 27,542 |
Year(s) Built / Renovated |  | 2001 |
Year(s) Acquired |  | 1998 |
Depreciable Lives (Years) | [3] | -1 |
Sumner Square |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |
Property Name |  | Sumner Square |
Type |  | Office |
Location |  | Washington, DC |
Encumbrances |  | $ 0 |
Original Land |  | 624 |
Original Building |  | 28,745 |
Costs Capitalized Subsequent to Acquisition |  | 19,054 |
Land and improvements |  | 1,478 |
Buildings and Improvements |  | 46,945 |
Land Held for Development |  | 0 |
Development and Construction in Progress |  | 0 |
Total |  | 48,423 |
Accumulated Depreciation |  | $ 25,384 |
Year(s) Built / Renovated |  | 1985 |
Year(s) Acquired |  | 1999 |
Depreciable Lives (Years) | [3] | -1 |
University Place |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |
Property Name |  | University Place |
Type |  | Office |
Location |  | Cambridge, MA |
Encumbrances |  | $ 5,571 |
Original Land |  | 0 |
Original Building |  | 37,091 |
Costs Capitalized Subsequent to Acquisition |  | 9,001 |
Land and improvements |  | 390 |
Buildings and Improvements |  | 45,702 |
Land Held for Development |  | 0 |
Development and Construction in Progress |  | 0 |
Total |  | 46,092 |
Accumulated Depreciation |  | $ 27,871 |
Year(s) Built / Renovated |  | 1985 |
Year(s) Acquired |  | 1998 |
Depreciable Lives (Years) | [3] | -1 |
2600 Tower Oaks Boulevard |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |
Property Name |  | 2600 Tower Oaks Boulevard |
Type |  | Office |
Location |  | Rockville, MD |
Encumbrances |  | $ 0 |
Original Land |  | 4,243 |
Original Building |  | 31,125 |
Costs Capitalized Subsequent to Acquisition |  | 6,517 |
Land and improvements |  | 4,244 |
Buildings and Improvements |  | 37,641 |
Land Held for Development |  | 0 |
Development and Construction in Progress |  | 0 |
Total |  | 41,885 |
Accumulated Depreciation |  | $ 21,426 |
Year(s) Built / Renovated |  | 2001 |
Year(s) Acquired |  | 1998 |
Depreciable Lives (Years) | [3] | -1 |
North First Business Park |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |
Property Name |  | North First Business Park |
Type |  | Office |
Location |  | San Jose, CA |
Encumbrances |  | $ 0 |
Original Land |  | 23,398 |
Original Building |  | 13,069 |
Costs Capitalized Subsequent to Acquisition |  | 4,613 |
Land and improvements |  | 23,377 |
Buildings and Improvements |  | 17,703 |
Land Held for Development |  | 0 |
Development and Construction in Progress |  | 0 |
Total |  | 41,080 |
Accumulated Depreciation |  | $ 16,076 |
Year(s) Built / Renovated |  | 1981 |
Year(s) Acquired |  | 2007 |
Depreciable Lives (Years) | [3] | -1 |
150 Broadway |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |
Property Name |  | 150 Broadway |
Type |  | Office |
Location |  | Cambridge, MA |
Encumbrances |  | $ 0 |
Original Land |  | 850 |
Original Building |  | 25,042 |
Costs Capitalized Subsequent to Acquisition |  | 8,540 |
Land and improvements |  | 1,323 |
Buildings and Improvements |  | 33,109 |
Land Held for Development |  | 0 |
Development and Construction in Progress |  | 0 |
Total |  | 34,432 |
Accumulated Depreciation |  | $ 18,404 |
Year(s) Built / Renovated |  | 1999 |
Year(s) Acquired |  | 1997 |
Depreciable Lives (Years) | [3] | -1 |
325 Main Street |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |
Property Name |  | 325 Main Street |
Type |  | Office |
Location |  | Cambridge, MA |
Encumbrances |  | $ 0 |
Original Land |  | 174 |
Original Building |  | 12,200 |
Costs Capitalized Subsequent to Acquisition |  | 16,437 |
Land and improvements |  | 965 |
Buildings and Improvements |  | 23,319 |
Land Held for Development |  | 4,527 |
Development and Construction in Progress |  | 0 |
Total |  | 28,811 |
Accumulated Depreciation |  | $ 13,676 |
Year(s) Built / Renovated |  | 1987/2013 |
Year(s) Acquired |  | 1997 |
Depreciable Lives (Years) | [3] | -1 |
105 Broadway |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |
Property Name |  | 105 Broadway |
Type |  | Office |
Location |  | Cambridge, MA |
Encumbrances |  | $ 0 |
Original Land |  | 1,299 |
Original Building |  | 12,943 |
Costs Capitalized Subsequent to Acquisition |  | 9,401 |
Land and improvements |  | 2,395 |
Buildings and Improvements |  | 21,248 |
Land Held for Development |  | 0 |
Development and Construction in Progress |  | 0 |
Total |  | 23,643 |
Accumulated Depreciation |  | $ 13,950 |
Year(s) Built / Renovated |  | 1990 |
Year(s) Acquired |  | 1997 |
Depreciable Lives (Years) | [3] | -1 |
Lexington Office Park |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |
Property Name |  | Lexington Office Park |
Type |  | Office |
Location |  | Lexington, MA |
Encumbrances |  | $ 0 |
Original Land |  | 998 |
Original Building |  | 1,426 |
Costs Capitalized Subsequent to Acquisition |  | 18,700 |
Land and improvements |  | 1,264 |
Buildings and Improvements |  | 19,860 |
Land Held for Development |  | 0 |
Development and Construction in Progress |  | 0 |
Total |  | 21,124 |
Accumulated Depreciation |  | $ 13,614 |
Year(s) Built / Renovated |  | 1982 |
Year(s) Acquired |  | 1997 |
Depreciable Lives (Years) | [3] | -1 |
201 Spring Street |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |
Property Name |  | 201 Spring Street |
Type |  | Office |
Location |  | Lexington, MA |
Encumbrances |  | $ 0 |
Original Land |  | 2,849 |
Original Building |  | 15,303 |
Costs Capitalized Subsequent to Acquisition |  | 1,390 |
Land and improvements |  | 3,124 |
Buildings and Improvements |  | 16,418 |
Land Held for Development |  | 0 |
Development and Construction in Progress |  | 0 |
Total |  | 19,542 |
Accumulated Depreciation |  | $ 8,344 |
Year(s) Built / Renovated |  | 1997 |
Year(s) Acquired |  | 1997 |
Depreciable Lives (Years) | [3] | -1 |
The Point |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |
Property Name |  | The Point |
Type |  | Office |
Location |  | Waltham, MA |
Encumbrances |  | $ 0 |
Original Land |  | 6,395 |
Original Building |  | 10,040 |
Costs Capitalized Subsequent to Acquisition |  | 431 |
Land and improvements |  | 6,480 |
Buildings and Improvements |  | 10,386 |
Land Held for Development |  | 0 |
Development and Construction in Progress |  | 0 |
Total |  | 16,866 |
Accumulated Depreciation |  | $ 1,031 |
Year(s) Built / Renovated |  | 2015 |
Year(s) Acquired |  | 2007 |
Depreciable Lives (Years) | [3] | -1 |
690 Folsom Street |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |
Property Name |  | 690 Folsom Street |
Type |  | Office |
Location |  | San Francisco, CA |
Encumbrances |  | $ 0 |
Original Land |  | 3,219 |
Original Building |  | 11,038 |
Costs Capitalized Subsequent to Acquisition |  | 1,157 |
Land and improvements |  | 3,219 |
Buildings and Improvements |  | 12,195 |
Land Held for Development |  | 0 |
Development and Construction in Progress |  | 0 |
Total |  | 15,414 |
Accumulated Depreciation |  | $ 1,790 |
Year(s) Built / Renovated |  | 2015 |
Year(s) Acquired |  | 2012 |
Depreciable Lives (Years) | [3] | -1 |
92-100 Hayden Avenue |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |
Property Name |  | 92-100 Hayden Avenue |
Type |  | Office |
Location |  | Lexington, MA |
Encumbrances |  | $ 0 |
Original Land |  | 594 |
Original Building |  | 6,748 |
Costs Capitalized Subsequent to Acquisition |  | 7,255 |
Land and improvements |  | 802 |
Buildings and Improvements |  | 13,795 |
Land Held for Development |  | 0 |
Development and Construction in Progress |  | 0 |
Total |  | 14,597 |
Accumulated Depreciation |  | $ 11,809 |
Year(s) Built / Renovated |  | 1985 |
Year(s) Acquired |  | 1997 |
Depreciable Lives (Years) | [3] | -1 |
181 Spring Street |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |
Property Name |  | 181 Spring Street |
Type |  | Office |
Location |  | Lexington, MA |
Encumbrances |  | $ 0 |
Original Land |  | 1,066 |
Original Building |  | 9,520 |
Costs Capitalized Subsequent to Acquisition |  | 2,230 |
Land and improvements |  | 1,160 |
Buildings and Improvements |  | 11,656 |
Land Held for Development |  | 0 |
Development and Construction in Progress |  | 0 |
Total |  | 12,816 |
Accumulated Depreciation |  | $ 5,424 |
Year(s) Built / Renovated |  | 1999 |
Year(s) Acquired |  | 1997 |
Depreciable Lives (Years) | [3] | -1 |
195 West Street |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |
Property Name |  | 195 West Street |
Type |  | Office |
Location |  | Waltham, MA |
Encumbrances |  | $ 0 |
Original Land |  | 1,611 |
Original Building |  | 6,652 |
Costs Capitalized Subsequent to Acquisition |  | 4,270 |
Land and improvements |  | 1,858 |
Buildings and Improvements |  | 10,675 |
Land Held for Development |  | 0 |
Development and Construction in Progress |  | 0 |
Total |  | 12,533 |
Accumulated Depreciation |  | $ 8,330 |
Year(s) Built / Renovated |  | 1990 |
Year(s) Acquired |  | 1997 |
Depreciable Lives (Years) | [3] | -1 |
33 Hayden Avenue |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |
Property Name |  | 33 Hayden Avenue |
Type |  | Office |
Location |  | Lexington, MA |
Encumbrances |  | $ 0 |
Original Land |  | 266 |
Original Building |  | 3,234 |
Costs Capitalized Subsequent to Acquisition |  | 8,223 |
Land and improvements |  | 425 |
Buildings and Improvements |  | 11,298 |
Land Held for Development |  | 0 |
Development and Construction in Progress |  | 0 |
Total |  | 11,723 |
Accumulated Depreciation |  | $ 9,033 |
Year(s) Built / Renovated |  | 1979 |
Year(s) Acquired |  | 1997 |
Depreciable Lives (Years) | [3] | -1 |
7501 Boston Boulevard, Building Seven |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |
Property Name |  | 7501 Boston Boulevard, Building Seven |
Type |  | Office |
Location |  | Springfield, VA |
Encumbrances |  | $ 0 |
Original Land |  | 665 |
Original Building |  | 9,273 |
Costs Capitalized Subsequent to Acquisition |  | 819 |
Land and improvements |  | 791 |
Buildings and Improvements |  | 9,966 |
Land Held for Development |  | 0 |
Development and Construction in Progress |  | 0 |
Total |  | 10,757 |
Accumulated Depreciation |  | $ 5,121 |
Year(s) Built / Renovated |  | 1997 |
Year(s) Acquired |  | 1997 |
Depreciable Lives (Years) | [3] | -1 |
7450 Boston Boulevard, Building Three |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |
Property Name |  | 7450 Boston Boulevard, Building Three |
Type |  | Office |
Location |  | Springfield, VA |
Encumbrances |  | $ 0 |
Original Land |  | 1,165 |
Original Building |  | 4,681 |
Costs Capitalized Subsequent to Acquisition |  | 3,278 |
Land and improvements |  | 1,430 |
Buildings and Improvements |  | 7,694 |
Land Held for Development |  | 0 |
Development and Construction in Progress |  | 0 |
Total |  | 9,124 |
Accumulated Depreciation |  | $ 3,733 |
Year(s) Built / Renovated |  | 1987 |
Year(s) Acquired |  | 1998 |
Depreciable Lives (Years) | [3] | -1 |
7435 Boston Boulevard, Building One |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |
Property Name |  | 7435 Boston Boulevard, Building One |
Type |  | Office |
Location |  | Springfield, VA |
Encumbrances |  | $ 0 |
Original Land |  | 392 |
Original Building |  | 3,822 |
Costs Capitalized Subsequent to Acquisition |  | 4,737 |
Land and improvements |  | 659 |
Buildings and Improvements |  | 8,292 |
Land Held for Development |  | 0 |
Development and Construction in Progress |  | 0 |
Total |  | 8,951 |
Accumulated Depreciation |  | $ 5,917 |
Year(s) Built / Renovated |  | 1982 |
Year(s) Acquired |  | 1997 |
Depreciable Lives (Years) | [3] | -1 |
250 Binney Street |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |
Property Name |  | 250 Binney Street |
Type |  | Office |
Location |  | Cambridge, MA |
Encumbrances |  | $ 0 |
Original Land |  | 110 |
Original Building |  | 4,483 |
Costs Capitalized Subsequent to Acquisition |  | 3,593 |
Land and improvements |  | 273 |
Buildings and Improvements |  | 7,913 |
Land Held for Development |  | 0 |
Development and Construction in Progress |  | 0 |
Total |  | 8,186 |
Accumulated Depreciation |  | $ 5,448 |
Year(s) Built / Renovated |  | 1983 |
Year(s) Acquired |  | 1997 |
Depreciable Lives (Years) | [3] | -1 |
8000 Grainger Court, Building Five |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |
Property Name |  | 8000 Grainger Court, Building Five |
Type |  | Office |
Location |  | Springfield, VA |
Encumbrances |  | $ 0 |
Original Land |  | 366 |
Original Building |  | 4,282 |
Costs Capitalized Subsequent to Acquisition |  | 3,536 |
Land and improvements |  | 601 |
Buildings and Improvements |  | 7,583 |
Land Held for Development |  | 0 |
Development and Construction in Progress |  | 0 |
Total |  | 8,184 |
Accumulated Depreciation |  | $ 5,864 |
Year(s) Built / Renovated |  | 1984 |
Year(s) Acquired |  | 1997 |
Depreciable Lives (Years) | [3] | -1 |
453 Ravendale Drive |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |
Property Name |  | 453 Ravendale Drive |
Type |  | Office |
Location |  | Mountain View, CA |
Encumbrances |  | $ 0 |
Original Land |  | 5,477 |
Original Building |  | 1,090 |
Costs Capitalized Subsequent to Acquisition |  | 676 |
Land and improvements |  | 5,477 |
Buildings and Improvements |  | 1,766 |
Land Held for Development |  | 0 |
Development and Construction in Progress |  | 0 |
Total |  | 7,243 |
Accumulated Depreciation |  | $ 558 |
Year(s) Built / Renovated |  | 1977 |
Year(s) Acquired |  | 2012 |
Depreciable Lives (Years) | [3] | -1 |
7300 Boston Boulevard, Building Thirteen |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |
Property Name |  | 7300 Boston Boulevard, Building Thirteen |
Type |  | Office |
Location |  | Springfield, VA |
Encumbrances |  | $ 0 |
Original Land |  | 608 |
Original Building |  | 4,773 |
Costs Capitalized Subsequent to Acquisition |  | 1,438 |
Land and improvements |  | 661 |
Buildings and Improvements |  | 6,158 |
Land Held for Development |  | 0 |
Development and Construction in Progress |  | 0 |
Total |  | 6,819 |
Accumulated Depreciation |  | $ 3,011 |
Year(s) Built / Renovated |  | 2002 |
Year(s) Acquired |  | 1997 |
Depreciable Lives (Years) | [3] | -1 |
7601 Boston Boulevard, Building Eight |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |
Property Name |  | 7601 Boston Boulevard, Building Eight |
Type |  | Office |
Location |  | Springfield, VA |
Encumbrances |  | $ 0 |
Original Land |  | 200 |
Original Building |  | 878 |
Costs Capitalized Subsequent to Acquisition |  | 5,373 |
Land and improvements |  | 551 |
Buildings and Improvements |  | 5,900 |
Land Held for Development |  | 0 |
Development and Construction in Progress |  | 0 |
Total |  | 6,451 |
Accumulated Depreciation |  | $ 4,487 |
Year(s) Built / Renovated |  | 1986 |
Year(s) Acquired |  | 1997 |
Depreciable Lives (Years) | [3] | -1 |
17 Hartwell Avenue |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |
Property Name |  | 17 Hartwell Avenue |
Type |  | Office |
Location |  | Lexington, MA |
Encumbrances |  | $ 0 |
Original Land |  | 26 |
Original Building |  | 150 |
Costs Capitalized Subsequent to Acquisition |  | 6,064 |
Land and improvements |  | 65 |
Buildings and Improvements |  | 6,175 |
Land Held for Development |  | 0 |
Development and Construction in Progress |  | 0 |
Total |  | 6,240 |
Accumulated Depreciation |  | $ 1,445 |
Year(s) Built / Renovated |  | 1968 |
Year(s) Acquired |  | 1997 |
Depreciable Lives (Years) | [3] | -1 |
7500 Boston Boulevard, Building Six |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |
Property Name |  | 7500 Boston Boulevard, Building Six |
Type |  | Office |
Location |  | Springfield, VA |
Encumbrances |  | $ 0 |
Original Land |  | 138 |
Original Building |  | 3,749 |
Costs Capitalized Subsequent to Acquisition |  | 1,673 |
Land and improvements |  | 406 |
Buildings and Improvements |  | 5,154 |
Land Held for Development |  | 0 |
Development and Construction in Progress |  | 0 |
Total |  | 5,560 |
Accumulated Depreciation |  | $ 4,121 |
Year(s) Built / Renovated |  | 1985 |
Year(s) Acquired |  | 1997 |
Depreciable Lives (Years) | [3] | -1 |
8000 Corporate Court, Building Eleven |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |
Property Name |  | 8000 Corporate Court, Building Eleven |
Type |  | Office |
Location |  | Springfield, VA |
Encumbrances |  | $ 0 |
Original Land |  | 136 |
Original Building |  | 3,071 |
Costs Capitalized Subsequent to Acquisition |  | 1,596 |
Land and improvements |  | 774 |
Buildings and Improvements |  | 4,029 |
Land Held for Development |  | 0 |
Development and Construction in Progress |  | 0 |
Total |  | 4,803 |
Accumulated Depreciation |  | $ 3,051 |
Year(s) Built / Renovated |  | 1989 |
Year(s) Acquired |  | 1997 |
Depreciable Lives (Years) | [3] | -1 |
7375 Boston Boulevard, Building Ten |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |
Property Name |  | 7375 Boston Boulevard, Building Ten |
Type |  | Office |
Location |  | Springfield, VA |
Encumbrances |  | $ 0 |
Original Land |  | 23 |
Original Building |  | 2,685 |
Costs Capitalized Subsequent to Acquisition |  | 992 |
Land and improvements |  | 93 |
Buildings and Improvements |  | 3,607 |
Land Held for Development |  | 0 |
Development and Construction in Progress |  | 0 |
Total |  | 3,700 |
Accumulated Depreciation |  | $ 2,593 |
Year(s) Built / Renovated |  | 1988 |
Year(s) Acquired |  | 1997 |
Depreciable Lives (Years) | [3] | -1 |
7374 Boston Boulevard, Building Four |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |
Property Name |  | 7374 Boston Boulevard, Building Four |
Type |  | Office |
Location |  | Springfield, VA |
Encumbrances |  | $ 0 |
Original Land |  | 241 |
Original Building |  | 1,605 |
Costs Capitalized Subsequent to Acquisition |  | 1,828 |
Land and improvements |  | 398 |
Buildings and Improvements |  | 3,276 |
Land Held for Development |  | 0 |
Development and Construction in Progress |  | 0 |
Total |  | 3,674 |
Accumulated Depreciation |  | $ 2,685 |
Year(s) Built / Renovated |  | 1984 |
Year(s) Acquired |  | 1997 |
Depreciable Lives (Years) | [3] | -1 |
7451 Boston Boulevard, Building Two |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |
Property Name |  | 7451 Boston Boulevard, Building Two |
Type |  | Office |
Location |  | Springfield, VA |
Encumbrances |  | $ 0 |
Original Land |  | 249 |
Original Building |  | 1,542 |
Costs Capitalized Subsequent to Acquisition |  | 1,659 |
Land and improvements |  | 613 |
Buildings and Improvements |  | 2,837 |
Land Held for Development |  | 0 |
Development and Construction in Progress |  | 0 |
Total |  | 3,450 |
Accumulated Depreciation |  | $ 2,527 |
Year(s) Built / Renovated |  | 1982 |
Year(s) Acquired |  | 1997 |
Depreciable Lives (Years) | [3] | -1 |
32 Hartwell Avenue |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |
Property Name |  | 32 Hartwell Avenue |
Type |  | Office |
Location |  | Lexington, MA |
Encumbrances |  | $ 0 |
Original Land |  | 168 |
Original Building |  | 1,943 |
Costs Capitalized Subsequent to Acquisition |  | 817 |
Land and improvements |  | 314 |
Buildings and Improvements |  | 2,614 |
Land Held for Development |  | 0 |
Development and Construction in Progress |  | 0 |
Total |  | 2,928 |
Accumulated Depreciation |  | $ 1,821 |
Year(s) Built / Renovated |  | 1968/1979/1987 |
Year(s) Acquired |  | 1997 |
Depreciable Lives (Years) | [3] | -1 |
164 Lexington Road |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |
Property Name |  | 164 Lexington Road |
Type |  | Office |
Location |  | Billerica, MA |
Encumbrances |  | $ 0 |
Original Land |  | 592 |
Original Building |  | 1,370 |
Costs Capitalized Subsequent to Acquisition |  | 319 |
Land and improvements |  | 643 |
Buildings and Improvements |  | 1,638 |
Land Held for Development |  | 0 |
Development and Construction in Progress |  | 0 |
Total |  | 2,281 |
Accumulated Depreciation |  | $ 906 |
Year(s) Built / Renovated |  | 1982 |
Year(s) Acquired |  | 1997 |
Depreciable Lives (Years) | [3] | -1 |
Signature at Reston |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |
Property Name |  | Signature at Reston |
Type |  | Residential |
Location |  | Reston, VA |
Encumbrances |  | $ 0 |
Original Land |  | 27,076 |
Original Building |  | 190,580 |
Costs Capitalized Subsequent to Acquisition |  | 0 |
Land and improvements |  | 27,076 |
Buildings and Improvements |  | 190,580 |
Land Held for Development |  | 0 |
Development and Construction in Progress |  | 0 |
Total |  | 217,656 |
Accumulated Depreciation |  | $ 3,938 |
Year(s) Built / Renovated |  | 2018 |
Year(s) Acquired |  | 2013 |
Depreciable Lives (Years) | [3] | -1 |
Proto Kendall Square |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |
Property Name |  | Proto Kendall Square |
Type |  | Residential |
Location |  | Cambridge, MA |
Encumbrances |  | $ 0 |
Original Land |  | 9,243 |
Original Building |  | 127,248 |
Costs Capitalized Subsequent to Acquisition |  | 0 |
Land and improvements |  | 9,243 |
Buildings and Improvements |  | 127,248 |
Land Held for Development |  | 0 |
Development and Construction in Progress |  | 0 |
Total |  | 136,491 |
Accumulated Depreciation |  | $ 1,324 |
Year(s) Built / Renovated |  | 2018 |
Year(s) Acquired |  | 2015 |
Depreciable Lives (Years) | [3] | -1 |
The Avant at Reston Town Center |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |
Property Name |  | The Avant at Reston Town Center |
Type |  | Residential |
Location |  | Reston, VA |
Encumbrances |  | $ 0 |
Original Land |  | 20,350 |
Original Building |  | 91,995 |
Costs Capitalized Subsequent to Acquisition |  | 830 |
Land and improvements |  | 20,350 |
Buildings and Improvements |  | 92,825 |
Land Held for Development |  | 0 |
Development and Construction in Progress |  | 0 |
Total |  | 113,175 |
Accumulated Depreciation |  | $ 12,254 |
Year(s) Built / Renovated |  | 2014 |
Year(s) Acquired |  | 2010 |
Depreciable Lives (Years) | [3] | -1 |
The Lofts at Atlantic Wharf |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |
Property Name |  | The Lofts at Atlantic Wharf |
Type |  | Residential |
Location |  | Boston, MA |
Encumbrances |  | $ 0 |
Original Land |  | 3,529 |
Original Building |  | 54,891 |
Costs Capitalized Subsequent to Acquisition |  | 1,768 |
Land and improvements |  | 3,529 |
Buildings and Improvements |  | 56,659 |
Land Held for Development |  | 0 |
Development and Construction in Progress |  | 0 |
Total |  | 60,188 |
Accumulated Depreciation |  | $ 11,131 |
Year(s) Built / Renovated |  | 2011 |
Year(s) Acquired |  | 2007 |
Depreciable Lives (Years) | [3] | -1 |
Boston Marriott Cambridge |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |
Property Name |  | Boston Marriott Cambridge |
Type |  | Hotel |
Location |  | Cambridge, MA |
Encumbrances |  | $ 0 |
Original Land |  | 478 |
Original Building |  | 37,918 |
Costs Capitalized Subsequent to Acquisition |  | 36,697 |
Land and improvements |  | 1,201 |
Buildings and Improvements |  | 73,892 |
Land Held for Development |  | 0 |
Development and Construction in Progress |  | 0 |
Total |  | 75,093 |
Accumulated Depreciation |  | $ 46,576 |
Year(s) Built / Renovated |  | 1986/2017 |
Year(s) Acquired |  | 1997 |
Depreciable Lives (Years) | [3] | -1 |
Kendall Center Green Garage |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |
Property Name |  | Kendall Center Green Garage |
Type |  | Garage |
Location |  | Cambridge, MA |
Encumbrances |  | $ 0 |
Original Land |  | 0 |
Original Building |  | 35,035 |
Costs Capitalized Subsequent to Acquisition |  | 7,448 |
Land and improvements |  | 103 |
Buildings and Improvements |  | 42,380 |
Land Held for Development |  | 0 |
Development and Construction in Progress |  | 0 |
Total |  | 42,483 |
Accumulated Depreciation |  | $ 12,208 |
Year(s) Built / Renovated |  | 1984 |
Year(s) Acquired |  | 2006 |
Depreciable Lives (Years) | [3] | -1 |
Kendall Center Yellow Garage |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |
Property Name |  | Kendall Center Yellow Garage |
Type |  | Garage |
Location |  | Cambridge, MA |
Encumbrances |  | $ 0 |
Original Land |  | 1,256 |
Original Building |  | 15,697 |
Costs Capitalized Subsequent to Acquisition |  | 1,621 |
Land and improvements |  | 1,434 |
Buildings and Improvements |  | 17,140 |
Land Held for Development |  | 0 |
Development and Construction in Progress |  | 0 |
Total |  | 18,574 |
Accumulated Depreciation |  | $ 5,643 |
Year(s) Built / Renovated |  | 2006 |
Year(s) Acquired |  | 2004 |
Depreciable Lives (Years) | [3] | -1 |
Kendall Center Blue Garage |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |
Property Name |  | Kendall Center Blue Garage |
Type |  | Garage |
Location |  | Cambridge, MA |
Encumbrances |  | $ 0 |
Original Land |  | 1,163 |
Original Building |  | 11,633 |
Costs Capitalized Subsequent to Acquisition |  | 2,145 |
Land and improvements |  | 1,579 |
Buildings and Improvements |  | 13,362 |
Land Held for Development |  | 0 |
Development and Construction in Progress |  | 0 |
Total |  | 14,941 |
Accumulated Depreciation |  | $ 9,437 |
Year(s) Built / Renovated |  | 1990 |
Year(s) Acquired |  | 1997 |
Depreciable Lives (Years) | [3] | -1 |
145 Broadway |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |
Property Name |  | 145 Broadway |
Type |  | Development |
Location |  | Cambridge, MA |
Encumbrances |  | $ 0 |
Original Land |  | 121 |
Original Building |  | 0 |
Costs Capitalized Subsequent to Acquisition |  | 223,845 |
Land and improvements |  | 324 |
Buildings and Improvements |  | 0 |
Land Held for Development |  | 0 |
Development and Construction in Progress |  | 223,642 |
Total |  | 223,966 |
Accumulated Depreciation |  | $ 0 |
Year(s) Built / Renovated |  | N/A |
Year(s) Acquired |  | 1997 |
Depreciable Lives (Years) |  | N/A |
MacArthur Station Residences |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |
Property Name |  | MacArthur Station Residences |
Type |  | Development |
Location |  | Oakland, CA |
Encumbrances |  | $ 0 |
Original Land |  | 0 |
Original Building |  | 0 |
Costs Capitalized Subsequent to Acquisition |  | 87,159 |
Land and improvements |  | 0 |
Buildings and Improvements |  | 0 |
Land Held for Development |  | 0 |
Development and Construction in Progress |  | 87,159 |
Total |  | 87,159 |
Accumulated Depreciation |  | $ 0 |
Year(s) Built / Renovated |  | N/A |
Year(s) Acquired |  | N/A |
Depreciable Lives (Years) |  | N/A |
20 CityPoint |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |
Property Name |  | 20 CityPoint |
Type |  | Development |
Location |  | Waltham, MA |
Encumbrances |  | $ 0 |
Original Land |  | 0 |
Original Building |  | 6,287 |
Costs Capitalized Subsequent to Acquisition |  | 46,024 |
Land and improvements |  | 0 |
Buildings and Improvements |  | 6,287 |
Land Held for Development |  | 0 |
Development and Construction in Progress |  | 46,024 |
Total |  | 52,311 |
Accumulated Depreciation |  | $ 0 |
Year(s) Built / Renovated |  | N/A |
Year(s) Acquired |  | 2007 |
Depreciable Lives (Years) |  | N/A |
Reston Gateway |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |
Property Name |  | Reston Gateway |
Type |  | Development |
Location |  | Reston, VA |
Encumbrances |  | $ 0 |
Original Land |  | 0 |
Original Building |  | 0 |
Costs Capitalized Subsequent to Acquisition |  | 25,167 |
Land and improvements |  | 0 |
Buildings and Improvements |  | 0 |
Land Held for Development |  | 0 |
Development and Construction in Progress |  | 25,167 |
Total |  | 25,167 |
Accumulated Depreciation |  | $ 0 |
Year(s) Built / Renovated |  | N/A |
Year(s) Acquired |  | 1998 |
Depreciable Lives (Years) |  | N/A |
17Fifty Presidents Street |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |
Property Name |  | 17Fifty Presidents Street |
Type |  | Development |
Location |  | Reston, VA |
Encumbrances |  | $ 0 |
Original Land |  | 0 |
Original Building |  | 0 |
Costs Capitalized Subsequent to Acquisition |  | 25,120 |
Land and improvements |  | 0 |
Buildings and Improvements |  | 0 |
Land Held for Development |  | 0 |
Development and Construction in Progress |  | 25,120 |
Total |  | 25,120 |
Accumulated Depreciation |  | $ 0 |
Year(s) Built / Renovated |  | N/A |
Year(s) Acquired |  | 2013 |
Depreciable Lives (Years) |  | N/A |
North First Master Plan |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |
Property Name |  | North First Master Plan |
Type |  | Land |
Location |  | San Jose, CA |
Encumbrances |  | $ 0 |
Original Land |  | 35,004 |
Original Building |  | 0 |
Costs Capitalized Subsequent to Acquisition |  | 3,932 |
Land and improvements |  | 0 |
Buildings and Improvements |  | 0 |
Land Held for Development |  | 38,936 |
Development and Construction in Progress |  | 0 |
Total |  | 38,936 |
Accumulated Depreciation |  | $ 0 |
Year(s) Built / Renovated |  | N/A |
Year(s) Acquired |  | 2007 |
Depreciable Lives (Years) |  | N/A |
Plaza at Almaden |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |
Property Name |  | Plaza at Almaden |
Type |  | Land |
Location |  | San Jose, CA |
Encumbrances |  | $ 0 |
Original Land |  | 0 |
Original Building |  | 0 |
Costs Capitalized Subsequent to Acquisition |  | 29,928 |
Land and improvements |  | 0 |
Buildings and Improvements |  | 0 |
Land Held for Development |  | 29,928 |
Development and Construction in Progress |  | 0 |
Total |  | 29,928 |
Accumulated Depreciation |  | $ 0 |
Year(s) Built / Renovated |  | N/A |
Year(s) Acquired |  | 2006 |
Depreciable Lives (Years) |  | N/A |
Springfield Metro Center |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |
Property Name |  | Springfield Metro Center |
Type |  | Land |
Location |  | Springfield, VA |
Encumbrances |  | $ 0 |
Original Land |  | 0 |
Original Building |  | 0 |
Costs Capitalized Subsequent to Acquisition |  | 19,823 |
Land and improvements |  | 0 |
Buildings and Improvements |  | 0 |
Land Held for Development |  | 19,823 |
Development and Construction in Progress |  | 0 |
Total |  | 19,823 |
Accumulated Depreciation |  | $ 0 |
Year(s) Built / Renovated |  | N/A |
Year(s) Acquired |  | 2007 |
Depreciable Lives (Years) |  | N/A |
214 Third Avenue |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |
Property Name |  | 214 Third Avenue |
Type |  | Land |
Location |  | Waltham, MA |
Encumbrances |  | $ 0 |
Original Land |  | 0 |
Original Building |  | 0 |
Costs Capitalized Subsequent to Acquisition |  | 15,233 |
Land and improvements |  | 0 |
Buildings and Improvements |  | 0 |
Land Held for Development |  | 15,233 |
Development and Construction in Progress |  | 0 |
Total |  | 15,233 |
Accumulated Depreciation |  | $ 0 |
Year(s) Built / Renovated |  | N/A |
Year(s) Acquired |  | 2006 |
Depreciable Lives (Years) |  | N/A |
Platform 16 |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |
Property Name |  | Platform 16 |
Type |  | Land |
Location |  | San Jose, CA |
Encumbrances |  | $ 0 |
Original Land |  | 0 |
Original Building |  | 0 |
Costs Capitalized Subsequent to Acquisition |  | 12,962 |
Land and improvements |  | 0 |
Buildings and Improvements |  | 0 |
Land Held for Development |  | 12,962 |
Development and Construction in Progress |  | 0 |
Total |  | 12,962 |
Accumulated Depreciation |  | $ 0 |
Year(s) Built / Renovated |  | N/A |
Year(s) Acquired |  | 2018 |
Depreciable Lives (Years) |  | N/A |
103 Fourth Avenue |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |
Property Name |  | 103 Fourth Avenue |
Type |  | Land |
Location |  | Waltham, MA |
Encumbrances |  | $ 0 |
Original Land |  | 0 |
Original Building |  | 0 |
Costs Capitalized Subsequent to Acquisition |  | 12,208 |
Land and improvements |  | 0 |
Buildings and Improvements |  | 0 |
Land Held for Development |  | 12,208 |
Development and Construction in Progress |  | 0 |
Total |  | 12,208 |
Accumulated Depreciation |  | $ 0 |
Year(s) Built / Renovated |  | N/A |
Year(s) Acquired |  | 2007 |
Depreciable Lives (Years) |  | N/A |
Reston Gateway Master Plan |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |
Property Name |  | Reston Gateway Master Plan |
Type |  | Land |
Location |  | Reston, VA |
Encumbrances |  | $ 0 |
Original Land |  | 0 |
Original Building |  | 0 |
Costs Capitalized Subsequent to Acquisition |  | 11,014 |
Land and improvements |  | 0 |
Buildings and Improvements |  | 0 |
Land Held for Development |  | 11,014 |
Development and Construction in Progress |  | 0 |
Total |  | 11,014 |
Accumulated Depreciation |  | $ 0 |
Year(s) Built / Renovated |  | N/A |
Year(s) Acquired |  | 1998 |
Depreciable Lives (Years) |  | N/A |
Fourth and Harrison |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |
Property Name |  | Fourth and Harrison |
Type |  | Land |
Location |  | San Francisco, CA |
Encumbrances |  | $ 0 |
Original Land |  | 0 |
Original Building |  | 0 |
Costs Capitalized Subsequent to Acquisition |  | 10,350 |
Land and improvements |  | 0 |
Buildings and Improvements |  | 0 |
Land Held for Development |  | 10,350 |
Development and Construction in Progress |  | 0 |
Total |  | 10,350 |
Accumulated Depreciation |  | $ 0 |
Year(s) Built / Renovated |  | N/A |
Year(s) Acquired |  | N/A |
Depreciable Lives (Years) |  | N/A |
2100 Pennsylvania Avenue |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |
Property Name |  | 2100 Pennsylvania Avenue |
Type |  | Land |
Location |  | Washington, DC |
Encumbrances |  | $ 0 |
Original Land |  | 0 |
Original Building |  | 0 |
Costs Capitalized Subsequent to Acquisition |  | 9,700 |
Land and improvements |  | 0 |
Buildings and Improvements |  | 0 |
Land Held for Development |  | 9,700 |
Development and Construction in Progress |  | 0 |
Total |  | 9,700 |
Accumulated Depreciation |  | $ 0 |
Year(s) Built / Renovated |  | N/A |
Year(s) Acquired |  | N/A |
Depreciable Lives (Years) |  | N/A |
Crane Meadow |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |
Property Name |  | Crane Meadow |
Type |  | Land |
Location |  | Marlborough, MA |
Encumbrances |  | $ 0 |
Original Land |  | 0 |
Original Building |  | 0 |
Costs Capitalized Subsequent to Acquisition |  | 8,852 |
Land and improvements |  | 0 |
Buildings and Improvements |  | 0 |
Land Held for Development |  | 8,852 |
Development and Construction in Progress |  | 0 |
Total |  | 8,852 |
Accumulated Depreciation |  | $ 0 |
Year(s) Built / Renovated |  | N/A |
Year(s) Acquired |  | 2000 |
Depreciable Lives (Years) |  | N/A |
Washingtonian North |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |
Property Name |  | Washingtonian North |
Type |  | Land |
Location |  | Gaithersburg, MD |
Encumbrances |  | $ 0 |
Original Land |  | 0 |
Original Building |  | 0 |
Costs Capitalized Subsequent to Acquisition |  | 7,473 |
Land and improvements |  | 0 |
Buildings and Improvements |  | 0 |
Land Held for Development |  | 7,473 |
Development and Construction in Progress |  | 0 |
Total |  | 7,473 |
Accumulated Depreciation |  | $ 0 |
Year(s) Built / Renovated |  | N/A |
Year(s) Acquired |  | 1998 |
Depreciable Lives (Years) |  | N/A |
Broad Run Business Park |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |
Property Name |  | Broad Run Business Park |
Type |  | Land |
Location |  | Loudoun County, VA |
Encumbrances |  | $ 0 |
Original Land |  | 0 |
Original Building |  | 0 |
Costs Capitalized Subsequent to Acquisition |  | 2,388 |
Land and improvements |  | 0 |
Buildings and Improvements |  | 0 |
Land Held for Development |  | 2,388 |
Development and Construction in Progress |  | 0 |
Total |  | 2,388 |
Accumulated Depreciation |  | $ 0 |
Year(s) Built / Renovated |  | N/A |
Year(s) Acquired |  | 1998 |
Depreciable Lives (Years) |  | N/A |
Kendall Center Master Plan |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |
Property Name |  | Kendall Center Master Plan |
Type |  | Land |
Location |  | Cambridge, MA |
Encumbrances |  | $ 0 |
Original Land |  | 0 |
Original Building |  | 0 |
Costs Capitalized Subsequent to Acquisition |  | 2,199 |
Land and improvements |  | 0 |
Buildings and Improvements |  | 0 |
Land Held for Development |  | 2,199 |
Development and Construction in Progress |  | 0 |
Total |  | 2,199 |
Accumulated Depreciation |  | $ 0 |
Year(s) Built / Renovated |  | N/A |
Year(s) Acquired |  | 1997 |
Depreciable Lives (Years) |  | N/A |
Weston Quarry |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |
Property Name |  | Weston Quarry |
Type |  | Land |
Location |  | Weston, MA |
Encumbrances |  | $ 0 |
Original Land |  | 0 |
Original Building |  | 0 |
Costs Capitalized Subsequent to Acquisition |  | 1,237 |
Land and improvements |  | 0 |
Buildings and Improvements |  | 0 |
Land Held for Development |  | 1,237 |
Development and Construction in Progress |  | 0 |
Total |  | 1,237 |
Accumulated Depreciation |  | $ 0 |
Year(s) Built / Renovated |  | N/A |
Year(s) Acquired |  | 2001 |
Depreciable Lives (Years) |  | N/A |
Reston Overlook Master Plan |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |
Property Name |  | Reston Overlook Master Plan |
Type |  | Land |
Location |  | Reston, VA |
Encumbrances |  | $ 0 |
Original Land |  | 0 |
Original Building |  | 0 |
Costs Capitalized Subsequent to Acquisition |  | 39 |
Land and improvements |  | 0 |
Buildings and Improvements |  | 0 |
Land Held for Development |  | 39 |
Development and Construction in Progress |  | 0 |
Total |  | 39 |
Accumulated Depreciation |  | $ 0 |
Year(s) Built / Renovated |  | N/A |
Year(s) Acquired |  | 2000 |
Depreciable Lives (Years) |  | N/A |
Minimum [Member] |  |  |
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] |  |  |
Life Used for Depreciation |  | life of the lease |
[1] | Includes unamortized deferred financing costs totaling approximately $(30.8) million.
[2] | Includes pre-development costs.
[3] | Depreciation of the buildings and improvements are calculated over lives ranging from the life of the lease to 40 years.

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