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SEC Schedule, Article 12-28, Real Estate and Accumulated Depreciation (Details) - USD ($) $ in Thousands | 12 Months Ended |  |  |  |
--- | --- | --- | --- | --- | ---
Dec. 31, 2021 | May 19, 2021 | Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |  |  |
Encumbrances |  | $ 3,267,914 |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | 5,238,614 |  |  |  |  |
Original Building |  | 13,216,859 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 5,652,747 |  |  |  |  |
Land and Improvements |  | 5,445,112 |  |  |  |  |
Building and Improvements |  | 17,208,581 |  |  |  |  |
Land held for development | [1] | 560,355 |  |  | $ 450,954 |  |
Development and Construction in Progress |  | 894,172 |  |  | 868,773 |  |
Total |  | 24,108,220 |  |  | 23,303,303 | $ 22,844,697 | $ 21,605,545
Accumulated Depreciation |  | 5,848,183 |  |  | 5,501,637 | 5,239,179 | 4,871,102
Furniture, Fixtures and Equipment |  | 51,695 |  |  | 49,606 |  |
Aggregate cost for tax purpose |  | 21,800,000 |  |  |  |  |
Real Estate Aggregate Accumulated Depreciation For Tax Purposes |  | 4,900,000 |  |  |  |  |
Debt Issuance Costs, Net |  | (32,086) |  |  |  |  |
Right-of-use assets - finance leases |  | 237,507 |  |  | 237,393 |  |
Right of use assets - operating leases |  | $ 169,778 | [2] |  | 146,406 |  |
Maximum [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Real Estate and Accumulated Depreciation, Life Used for Depreciation |  | 40 years |  |  |  |  |
Furniture, fixtures, and equipment |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Accumulated Depreciation Related to Furniture, Fixtures and Equipment |  | $ 35,778 |  |  |  |  |
Land and Land Improvements [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Right-of-use assets - finance leases |  | 214,165 |  |  |  |  |
Right of use assets - operating leases |  | 169,778 |  |  |  |  |
Buildings and improvements |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Right-of-use assets - finance leases |  | 23,342 |  |  |  |  |
Boston Properties Limited Partnership |  |  |  |  |  |  |
SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |  |  |
Encumbrances | [3] | 3,267,914 |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | 5,238,614 |  |  |  |  |
Original Building |  | 13,216,859 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 5,279,360 |  |  |  |  |
Land and Improvements | [4] | 5,348,929 |  |  |  |  |
Building and Improvements | [5] | 16,931,377 |  |  |  |  |
Land held for development | [1] | 560,355 |  |  | 450,954 |  |
Development and Construction in Progress |  | 894,172 |  |  | 868,773 |  |
Total |  | 23,734,833 |  |  | 22,926,494 | 22,449,476 | 21,207,189
Accumulated Depreciation |  | 5,736,240 |  |  | 5,396,111 | $ 5,135,289 | $ 4,773,800
Furniture, Fixtures and Equipment |  | 51,695 |  |  | 49,606 |  |
Aggregate cost for tax purpose |  | 24,200,000 |  |  |  |  |
Real Estate Aggregate Accumulated Depreciation For Tax Purposes |  | 5,400,000 |  |  |  |  |
Debt Issuance Costs, Net |  | (32,100) |  |  |  |  |
Right-of-use assets - finance leases |  | 237,507 |  |  | 237,393 |  |
Right of use assets - operating leases |  | $ 169,778 | [2] |  | $ 146,406 |  |
Boston Properties Limited Partnership | Maximum [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Real Estate and Accumulated Depreciation, Life Used for Depreciation |  | 40 years |  |  |  |  |
Boston Properties Limited Partnership | Furniture, fixtures, and equipment |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Accumulated Depreciation Related to Furniture, Fixtures and Equipment |  | $ 35,778 |  |  |  |  |
Boston Properties Limited Partnership | Land and Land Improvements [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Right-of-use assets - finance leases |  | 214,165 |  |  |  |  |
Right of use assets - operating leases |  | 169,778 |  |  |  |  |
Boston Properties Limited Partnership | Buildings and improvements |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Right-of-use assets - finance leases |  | 23,342 |  |  |  |  |
767Fifth Avenue (the General Motors Building) | Office Building [Member] |  |  |  |  |  |  |
SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |  |  |
Encumbrances |  | 2,281,016 |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | 1,796,252 |  |  |  |  |
Original Building |  | 1,532,654 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 260,700 |  |  |  |  |
Land and Improvements |  | 1,796,252 |  |  |  |  |
Building and Improvements |  | 1,793,354 |  |  |  |  |
Total |  | 3,589,606 |  |  |  |  |
Accumulated Depreciation |  | $ 407,377 |  |  |  |  |
Depreciable Lives (Years) | [6] | (1) |  |  |  |  |
767Fifth Avenue (the General Motors Building) | Boston Properties Limited Partnership | Office Building [Member] |  |  |  |  |  |  |
SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |  |  |
Encumbrances |  | $ 2,281,016 |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | 1,796,252 |  |  |  |  |
Original Building |  | 1,532,654 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 260,700 |  |  |  |  |
Land and Improvements |  | 1,796,252 |  |  |  |  |
Building and Improvements |  | 1,793,354 |  |  |  |  |
Total |  | 3,589,606 |  |  |  |  |
Accumulated Depreciation |  | $ 407,377 |  |  |  |  |
Depreciable Lives (Years) | [7] | (1) |  |  |  |  |
Prudential Center | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 92,077 |  |  |  |  |
Original Building |  | 948,357 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 615,973 |  |  |  |  |
Land and Improvements |  | 115,637 |  |  |  |  |
Building and Improvements |  | 1,483,065 |  |  |  |  |
Land held for development |  | 192 |  |  |  |  |
Development and Construction in Progress |  | 57,513 |  |  |  |  |
Total |  | 1,656,407 |  |  |  |  |
Accumulated Depreciation |  | $ 678,000 |  |  |  |  |
Depreciable Lives (Years) | [6] | (1) |  |  |  |  |
Prudential Center | Boston Properties Limited Partnership | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 92,077 |  |  |  |  |
Original Building |  | 948,357 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 556,917 |  |  |  |  |
Land and Improvements |  | 100,539 |  |  |  |  |
Building and Improvements |  | 1,439,107 |  |  |  |  |
Land held for development |  | 192 |  |  |  |  |
Development and Construction in Progress |  | 57,513 |  |  |  |  |
Total |  | 1,597,351 |  |  |  |  |
Accumulated Depreciation |  | $ 660,321 |  |  |  |  |
Depreciable Lives (Years) | [7] | (1) |  |  |  |  |
Embarcadero Center | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 179,697 |  |  |  |  |
Original Building |  | 847,410 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 480,465 |  |  |  |  |
Land and Improvements |  | 195,987 |  |  |  |  |
Building and Improvements |  | 1,311,585 |  |  |  |  |
Total |  | 1,507,572 |  |  |  |  |
Accumulated Depreciation |  | $ 692,283 |  |  |  |  |
Depreciable Lives (Years) | [6] | (1) |  |  |  |  |
Embarcadero Center | Boston Properties Limited Partnership | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 179,697 |  |  |  |  |
Original Building |  | 847,410 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 418,084 |  |  |  |  |
Land and Improvements |  | 180,420 |  |  |  |  |
Building and Improvements |  | 1,264,771 |  |  |  |  |
Total |  | 1,445,191 |  |  |  |  |
Accumulated Depreciation |  | $ 673,363 |  |  |  |  |
Depreciable Lives (Years) | [7] | (1) |  |  |  |  |
399 Park Avenue | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 339,200 |  |  |  |  |
Original Building |  | 700,358 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 366,449 |  |  |  |  |
Land and Improvements |  | 354,107 |  |  |  |  |
Building and Improvements |  | 1,051,900 |  |  |  |  |
Total |  | 1,406,007 |  |  |  |  |
Accumulated Depreciation |  | $ 405,104 |  |  |  |  |
Depreciable Lives (Years) | [6] | (1) |  |  |  |  |
399 Park Avenue | Boston Properties Limited Partnership | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 339,200 |  |  |  |  |
Original Building |  | 700,358 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 306,841 |  |  |  |  |
Land and Improvements |  | 339,200 |  |  |  |  |
Building and Improvements |  | 1,007,199 |  |  |  |  |
Total |  | 1,346,399 |  |  |  |  |
Accumulated Depreciation |  | $ 387,131 |  |  |  |  |
Depreciable Lives (Years) | [7] | (1) |  |  |  |  |
601 Lexington Avenue | Office Building [Member] |  |  |  |  |  |  |
SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |  |  |
Encumbrances |  | $ 986,898 |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | 241,600 |  |  |  |  |
Original Building |  | 494,782 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 486,028 |  |  |  |  |
Land and Improvements |  | 289,639 |  |  |  |  |
Building and Improvements |  | 932,771 |  |  |  |  |
Total |  | 1,222,410 |  |  |  |  |
Accumulated Depreciation |  | $ 325,012 |  |  |  |  |
Depreciable Lives (Years) | [6] | (1) |  |  |  |  |
601 Lexington Avenue | Boston Properties Limited Partnership | Office Building [Member] |  |  |  |  |  |  |
SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |  |  |
Encumbrances |  | $ 986,898 |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | 241,600 |  |  |  |  |
Original Building |  | 494,782 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 448,942 |  |  |  |  |
Land and Improvements |  | 279,281 |  |  |  |  |
Building and Improvements |  | 906,043 |  |  |  |  |
Total |  | 1,185,324 |  |  |  |  |
Accumulated Depreciation |  | $ 314,209 |  |  |  |  |
Depreciable Lives (Years) | [7] | (1) |  |  |  |  |
Salesforce Tower | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 200,349 |  |  |  |  |
Original Building |  | 946,205 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 7,515 |  |  |  |  |
Land and Improvements |  | 200,349 |  |  |  |  |
Building and Improvements |  | 953,720 |  |  |  |  |
Total |  | 1,154,069 |  |  |  |  |
Accumulated Depreciation |  | $ 99,152 |  |  |  |  |
Depreciable Lives (Years) | [6] | (1) |  |  |  |  |
Salesforce Tower | Boston Properties Limited Partnership | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 200,349 |  |  |  |  |
Original Building |  | 946,205 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 7,515 |  |  |  |  |
Land and Improvements |  | 200,349 |  |  |  |  |
Building and Improvements |  | 953,720 |  |  |  |  |
Total |  | 1,154,069 |  |  |  |  |
Accumulated Depreciation |  | $ 99,152 |  |  |  |  |
Depreciable Lives (Years) | [7] | (1) |  |  |  |  |
200 Clarendon Street and Garage | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 219,543 |  |  |  |  |
Original Building |  | 667,884 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 222,640 |  |  |  |  |
Land and Improvements |  | 250,560 |  |  |  |  |
Building and Improvements |  | 859,507 |  |  |  |  |
Total |  | 1,110,067 |  |  |  |  |
Accumulated Depreciation |  | $ 277,388 |  |  |  |  |
Depreciable Lives (Years) | [6] | (1) |  |  |  |  |
200 Clarendon Street and Garage | Boston Properties Limited Partnership | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 219,543 |  |  |  |  |
Original Building |  | 667,884 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 222,640 |  |  |  |  |
Land and Improvements |  | 250,560 |  |  |  |  |
Building and Improvements |  | 859,507 |  |  |  |  |
Total |  | 1,110,067 |  |  |  |  |
Accumulated Depreciation |  | $ 277,388 |  |  |  |  |
Depreciable Lives (Years) | [7] | (1) |  |  |  |  |
250 West 55th Street | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 285,263 |  |  |  |  |
Original Building |  | 603,167 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 52,298 |  |  |  |  |
Land and Improvements |  | 285,263 |  |  |  |  |
Building and Improvements |  | 655,465 |  |  |  |  |
Total |  | 940,728 |  |  |  |  |
Accumulated Depreciation |  | $ 159,238 |  |  |  |  |
Depreciable Lives (Years) | [6] | (1) |  |  |  |  |
250 West 55th Street | Boston Properties Limited Partnership | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 285,263 |  |  |  |  |
Original Building |  | 603,167 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 52,298 |  |  |  |  |
Land and Improvements |  | 285,263 |  |  |  |  |
Building and Improvements |  | 655,465 |  |  |  |  |
Total |  | 940,728 |  |  |  |  |
Accumulated Depreciation |  | $ 159,238 |  |  |  |  |
Depreciable Lives (Years) | [7] | (1) |  |  |  |  |
100 Federal Street | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 131,067 |  |  |  |  |
Original Building |  | 435,954 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 138,727 |  |  |  |  |
Land and Improvements |  | 131,067 |  |  |  |  |
Building and Improvements |  | 574,681 |  |  |  |  |
Total |  | 705,748 |  |  |  |  |
Accumulated Depreciation |  | $ 157,939 |  |  |  |  |
Depreciable Lives (Years) | [6] | (1) |  |  |  |  |
100 Federal Street | Boston Properties Limited Partnership | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 131,067 |  |  |  |  |
Original Building |  | 435,954 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 138,727 |  |  |  |  |
Land and Improvements |  | 131,067 |  |  |  |  |
Building and Improvements |  | 574,681 |  |  |  |  |
Total |  | 705,748 |  |  |  |  |
Accumulated Depreciation |  | $ 157,939 |  |  |  |  |
Depreciable Lives (Years) | [7] | (1) |  |  |  |  |
Times Square Tower | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 165,413 |  |  |  |  |
Original Building |  | 380,438 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 115,843 |  |  |  |  |
Land and Improvements |  | 169,193 |  |  |  |  |
Building and Improvements |  | 492,501 |  |  |  |  |
Total |  | 661,694 |  |  |  |  |
Accumulated Depreciation |  | $ 232,128 |  |  |  |  |
Depreciable Lives (Years) | [6] | (1) |  |  |  |  |
Times Square Tower | Boston Properties Limited Partnership | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 165,413 |  |  |  |  |
Original Building |  | 380,438 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 77,864 |  |  |  |  |
Land and Improvements |  | 159,694 |  |  |  |  |
Building and Improvements |  | 464,021 |  |  |  |  |
Total |  | 623,715 |  |  |  |  |
Accumulated Depreciation |  | $ 220,676 |  |  |  |  |
Depreciable Lives (Years) | [7] | (1) |  |  |  |  |
Carnegie Center | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 142,666 |  |  |  |  |
Original Building |  | 316,856 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 159,350 |  |  |  |  |
Land and Improvements |  | 94,240 |  |  |  |  |
Building and Improvements |  | 469,216 |  |  |  |  |
Land held for development |  | 55,416 |  |  |  |  |
Total |  | 618,872 |  |  |  |  |
Accumulated Depreciation |  | $ 236,695 |  |  |  |  |
Depreciable Lives (Years) | [6] | (1) |  |  |  |  |
Carnegie Center | Boston Properties Limited Partnership | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 142,666 |  |  |  |  |
Original Building |  | 316,856 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 144,387 |  |  |  |  |
Land and Improvements |  | 90,498 |  |  |  |  |
Building and Improvements |  | 457,995 |  |  |  |  |
Land held for development |  | 55,416 |  |  |  |  |
Total |  | 603,909 |  |  |  |  |
Accumulated Depreciation |  | $ 232,183 |  |  |  |  |
Depreciable Lives (Years) | [7] | (1) |  |  |  |  |
Atlantic Wharf | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 63,988 |  |  |  |  |
Original Building |  | 454,537 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 19,831 |  |  |  |  |
Land and Improvements |  | 63,988 |  |  |  |  |
Building and Improvements |  | 474,368 |  |  |  |  |
Total |  | 538,356 |  |  |  |  |
Accumulated Depreciation |  | $ 156,879 |  |  |  |  |
Depreciable Lives (Years) | [6] | (1) |  |  |  |  |
Atlantic Wharf | Boston Properties Limited Partnership | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 63,988 |  |  |  |  |
Original Building |  | 454,537 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 19,831 |  |  |  |  |
Land and Improvements |  | 63,988 |  |  |  |  |
Building and Improvements |  | 474,368 |  |  |  |  |
Total |  | 538,356 |  |  |  |  |
Accumulated Depreciation |  | $ 156,879 |  |  |  |  |
Depreciable Lives (Years) | [7] | (1) |  |  |  |  |
599 Lexington Avenue | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 81,040 |  |  |  |  |
Original Building |  | 100,507 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 247,001 |  |  |  |  |
Land and Improvements |  | 87,852 |  |  |  |  |
Building and Improvements |  | 340,696 |  |  |  |  |
Total |  | 428,548 |  |  |  |  |
Accumulated Depreciation |  | $ 179,928 |  |  |  |  |
Depreciable Lives (Years) | [6] | (1) |  |  |  |  |
599 Lexington Avenue | Boston Properties Limited Partnership | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 81,040 |  |  |  |  |
Original Building |  | 100,507 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 219,759 |  |  |  |  |
Land and Improvements |  | 81,040 |  |  |  |  |
Building and Improvements |  | 320,266 |  |  |  |  |
Total |  | 401,306 |  |  |  |  |
Accumulated Depreciation |  | $ 171,713 |  |  |  |  |
Depreciable Lives (Years) | [7] | (1) |  |  |  |  |
Fountain Square | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 56,853 |  |  |  |  |
Original Building |  | 306,298 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 29,595 |  |  |  |  |
Land and Improvements |  | 56,853 |  |  |  |  |
Building and Improvements |  | 335,893 |  |  |  |  |
Total |  | 392,746 |  |  |  |  |
Accumulated Depreciation |  | $ 94,501 |  |  |  |  |
Depreciable Lives (Years) | [6] | (1) |  |  |  |  |
Fountain Square | Boston Properties Limited Partnership | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 56,853 |  |  |  |  |
Original Building |  | 306,298 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 29,595 |  |  |  |  |
Land and Improvements |  | 56,853 |  |  |  |  |
Building and Improvements |  | 335,893 |  |  |  |  |
Total |  | 392,746 |  |  |  |  |
Accumulated Depreciation |  | $ 94,501 |  |  |  |  |
Depreciable Lives (Years) | [7] | (1) |  |  |  |  |
510 Madison Avenue | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 103,000 |  |  |  |  |
Original Building |  | 253,665 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 28,825 |  |  |  |  |
Land and Improvements |  | 103,000 |  |  |  |  |
Building and Improvements |  | 282,490 |  |  |  |  |
Total |  | 385,490 |  |  |  |  |
Accumulated Depreciation |  | $ 90,673 |  |  |  |  |
Depreciable Lives (Years) | [6] | (1) |  |  |  |  |
510 Madison Avenue | Boston Properties Limited Partnership | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 103,000 |  |  |  |  |
Original Building |  | 253,665 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 28,825 |  |  |  |  |
Land and Improvements |  | 103,000 |  |  |  |  |
Building and Improvements |  | 282,490 |  |  |  |  |
Total |  | 385,490 |  |  |  |  |
Accumulated Depreciation |  | $ 90,673 |  |  |  |  |
Depreciable Lives (Years) | [7] | (1) |  |  |  |  |
680 Folsom Street | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 72,545 |  |  |  |  |
Original Building |  | 219,766 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 8,026 |  |  |  |  |
Land and Improvements |  | 72,545 |  |  |  |  |
Building and Improvements |  | 227,792 |  |  |  |  |
Total |  | 300,337 |  |  |  |  |
Accumulated Depreciation |  | $ 63,864 |  |  |  |  |
Depreciable Lives (Years) | [6] | (1) |  |  |  |  |
680 Folsom Street | Boston Properties Limited Partnership | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 72,545 |  |  |  |  |
Original Building |  | 219,766 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 8,026 |  |  |  |  |
Land and Improvements |  | 72,545 |  |  |  |  |
Building and Improvements |  | 227,792 |  |  |  |  |
Total |  | 300,337 |  |  |  |  |
Accumulated Depreciation |  | $ 63,864 |  |  |  |  |
Depreciable Lives (Years) | [7] | (1) |  |  |  |  |
145 Broadway | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 121 |  |  |  |  |
Original Building |  | 273,013 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 25,992 |  |  |  |  |
Land and Improvements |  | 23,367 |  |  |  |  |
Building and Improvements |  | 275,759 |  |  |  |  |
Total |  | 299,126 |  |  |  |  |
Accumulated Depreciation |  | $ 18,393 |  |  |  |  |
Depreciable Lives (Years) | [6] | (1) |  |  |  |  |
145 Broadway | Boston Properties Limited Partnership | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 121 |  |  |  |  |
Original Building |  | 273,013 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 25,789 |  |  |  |  |
Land and Improvements |  | 23,164 |  |  |  |  |
Building and Improvements |  | 275,759 |  |  |  |  |
Total |  | 298,923 |  |  |  |  |
Accumulated Depreciation |  | $ 18,393 |  |  |  |  |
Depreciable Lives (Years) | [7] | (1) |  |  |  |  |
2200 Pennsylvania Avenue | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 0 |  |  |  |  |
Original Building |  | 183,541 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 110,980 |  |  |  |  |
Land and Improvements |  | 105,787 |  |  |  |  |
Building and Improvements |  | 188,734 |  |  |  |  |
Total |  | 294,521 |  |  |  |  |
Accumulated Depreciation |  | $ 71,983 |  |  |  |  |
Depreciable Lives (Years) | [6] | (1) |  |  |  |  |
2200 Pennsylvania Avenue | Boston Properties Limited Partnership | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 0 |  |  |  |  |
Original Building |  | 183,541 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 110,980 |  |  |  |  |
Land and Improvements |  | 105,787 |  |  |  |  |
Building and Improvements |  | 188,734 |  |  |  |  |
Total |  | 294,521 |  |  |  |  |
Accumulated Depreciation |  | $ 71,983 |  |  |  |  |
Depreciable Lives (Years) | [7] | (1) |  |  |  |  |
South of Market and Democracy Tower | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 13,603 |  |  |  |  |
Original Building |  | 237,479 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 21,882 |  |  |  |  |
Land and Improvements |  | 13,687 |  |  |  |  |
Building and Improvements |  | 259,277 |  |  |  |  |
Total |  | 272,964 |  |  |  |  |
Accumulated Depreciation |  | $ 94,354 |  |  |  |  |
Depreciable Lives (Years) | [6] | (1) |  |  |  |  |
South of Market and Democracy Tower | Boston Properties Limited Partnership | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 13,603 |  |  |  |  |
Original Building |  | 237,479 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 21,546 |  |  |  |  |
Land and Improvements |  | 13,603 |  |  |  |  |
Building and Improvements |  | 259,025 |  |  |  |  |
Total |  | 272,628 |  |  |  |  |
Accumulated Depreciation |  | $ 94,269 |  |  |  |  |
Depreciable Lives (Years) | [7] | (1) |  |  |  |  |
601 Massachusetts Avenue | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 95,310 |  |  |  |  |
Original Building |  | 165,173 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 3,965 |  |  |  |  |
Land and Improvements |  | 95,322 |  |  |  |  |
Building and Improvements |  | 169,126 |  |  |  |  |
Total |  | 264,448 |  |  |  |  |
Accumulated Depreciation |  | $ 36,983 |  |  |  |  |
Depreciable Lives (Years) | [6] | (1) |  |  |  |  |
601 Massachusetts Avenue | Boston Properties Limited Partnership | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 95,310 |  |  |  |  |
Original Building |  | 165,173 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 3,953 |  |  |  |  |
Land and Improvements |  | 95,310 |  |  |  |  |
Building and Improvements |  | 169,126 |  |  |  |  |
Total |  | 264,436 |  |  |  |  |
Accumulated Depreciation |  | $ 36,983 |  |  |  |  |
Depreciable Lives (Years) | [7] | (1) |  |  |  |  |
Bay Colony Corporate Center | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 18,789 |  |  |  |  |
Original Building |  | 148,451 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 80,753 |  |  |  |  |
Land and Improvements |  | 18,789 |  |  |  |  |
Building and Improvements |  | 229,144 |  |  |  |  |
Land held for development |  | 60 |  |  |  |  |
Total |  | 247,993 |  |  |  |  |
Accumulated Depreciation |  | $ 97,149 |  |  |  |  |
Depreciable Lives (Years) | [6] | (1) |  |  |  |  |
Bay Colony Corporate Center | Boston Properties Limited Partnership | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 18,789 |  |  |  |  |
Original Building |  | 148,451 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 80,753 |  |  |  |  |
Land and Improvements |  | 18,789 |  |  |  |  |
Building and Improvements |  | 229,144 |  |  |  |  |
Land held for development |  | 60 |  |  |  |  |
Total |  | 247,993 |  |  |  |  |
Accumulated Depreciation |  | $ 97,149 |  |  |  |  |
Depreciable Lives (Years) | [7] | (1) |  |  |  |  |
535 Mission Street | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 40,933 |  |  |  |  |
Original Building |  | 148,378 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 3,501 |  |  |  |  |
Land and Improvements |  | 40,933 |  |  |  |  |
Building and Improvements |  | 151,879 |  |  |  |  |
Total |  | 192,812 |  |  |  |  |
Accumulated Depreciation |  | $ 37,477 |  |  |  |  |
Depreciable Lives (Years) | [6] | (1) |  |  |  |  |
535 Mission Street | Boston Properties Limited Partnership | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 40,933 |  |  |  |  |
Original Building |  | 148,378 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 3,501 |  |  |  |  |
Land and Improvements |  | 40,933 |  |  |  |  |
Building and Improvements |  | 151,879 |  |  |  |  |
Total |  | 192,812 |  |  |  |  |
Accumulated Depreciation |  | $ 37,477 |  |  |  |  |
Depreciable Lives (Years) | [7] | (1) |  |  |  |  |
Mountain View Research Park | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 95,066 |  |  |  |  |
Original Building |  | 68,373 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 16,801 |  |  |  |  |
Land and Improvements |  | 95,066 |  |  |  |  |
Building and Improvements |  | 85,174 |  |  |  |  |
Total |  | 180,240 |  |  |  |  |
Accumulated Depreciation |  | $ 24,149 |  |  |  |  |
Depreciable Lives (Years) | [6] | (1) |  |  |  |  |
Mountain View Research Park | Boston Properties Limited Partnership | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 95,066 |  |  |  |  |
Original Building |  | 68,373 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 16,801 |  |  |  |  |
Land and Improvements |  | 95,066 |  |  |  |  |
Building and Improvements |  | 85,174 |  |  |  |  |
Total |  | 180,240 |  |  |  |  |
Accumulated Depreciation |  | $ 24,149 |  |  |  |  |
Depreciable Lives (Years) | [7] | (1) |  |  |  |  |
Reservoir Place | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 18,605 |  |  |  |  |
Original Building |  | 104,124 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 53,945 |  |  |  |  |
Land and Improvements |  | 20,108 |  |  |  |  |
Building and Improvements |  | 156,275 |  |  |  |  |
Land held for development |  | 291 |  |  |  |  |
Total |  | 176,674 |  |  |  |  |
Accumulated Depreciation |  | $ 79,338 |  |  |  |  |
Depreciable Lives (Years) | [6] | (1) |  |  |  |  |
Reservoir Place | Boston Properties Limited Partnership | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 18,605 |  |  |  |  |
Original Building |  | 104,124 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 49,870 |  |  |  |  |
Land and Improvements |  | 19,089 |  |  |  |  |
Building and Improvements |  | 153,219 |  |  |  |  |
Land held for development |  | 291 |  |  |  |  |
Total |  | 172,599 |  |  |  |  |
Accumulated Depreciation |  | $ 78,109 |  |  |  |  |
Depreciable Lives (Years) | [7] | (1) |  |  |  |  |
1330 Connecticut Avenue | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 25,982 |  |  |  |  |
Original Building |  | 82,311 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 37,161 |  |  |  |  |
Land and Improvements |  | 27,135 |  |  |  |  |
Building and Improvements |  | 118,319 |  |  |  |  |
Total |  | 145,454 |  |  |  |  |
Accumulated Depreciation |  | $ 43,174 |  |  |  |  |
Depreciable Lives (Years) | [6] | (1) |  |  |  |  |
1330 Connecticut Avenue | Boston Properties Limited Partnership | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 25,982 |  |  |  |  |
Original Building |  | 82,311 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 32,548 |  |  |  |  |
Land and Improvements |  | 25,982 |  |  |  |  |
Building and Improvements |  | 114,859 |  |  |  |  |
Total |  | 140,841 |  |  |  |  |
Accumulated Depreciation |  | $ 41,783 |  |  |  |  |
Depreciable Lives (Years) | [7] | (1) |  |  |  |  |
One Freedom Square | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 9,929 |  |  |  |  |
Original Building |  | 84,504 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 41,978 |  |  |  |  |
Land and Improvements |  | 11,293 |  |  |  |  |
Building and Improvements |  | 125,118 |  |  |  |  |
Total |  | 136,411 |  |  |  |  |
Accumulated Depreciation |  | $ 60,550 |  |  |  |  |
Depreciable Lives (Years) | [6] | (1) |  |  |  |  |
One Freedom Square | Boston Properties Limited Partnership | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 9,929 |  |  |  |  |
Original Building |  | 84,504 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 36,341 |  |  |  |  |
Land and Improvements |  | 9,883 |  |  |  |  |
Building and Improvements |  | 120,891 |  |  |  |  |
Total |  | 130,774 |  |  |  |  |
Accumulated Depreciation |  | $ 58,850 |  |  |  |  |
Depreciable Lives (Years) | [7] | (1) |  |  |  |  |
Kingstowne Towne Center | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 18,021 |  |  |  |  |
Original Building |  | 109,038 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 3,875 |  |  |  |  |
Land and Improvements |  | 18,062 |  |  |  |  |
Building and Improvements |  | 112,872 |  |  |  |  |
Total |  | 130,934 |  |  |  |  |
Accumulated Depreciation |  | $ 49,475 |  |  |  |  |
Depreciable Lives (Years) | [6] | (1) |  |  |  |  |
Kingstowne Towne Center | Boston Properties Limited Partnership | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 18,021 |  |  |  |  |
Original Building |  | 109,038 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 3,711 |  |  |  |  |
Land and Improvements |  | 18,021 |  |  |  |  |
Building and Improvements |  | 112,749 |  |  |  |  |
Total |  | 130,770 |  |  |  |  |
Accumulated Depreciation |  | $ 49,433 |  |  |  |  |
Depreciable Lives (Years) | [7] | (1) |  |  |  |  |
One and Two Reston Overlook | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 16,456 |  |  |  |  |
Original Building |  | 66,192 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 40,694 |  |  |  |  |
Land and Improvements |  | 16,179 |  |  |  |  |
Building and Improvements |  | 107,163 |  |  |  |  |
Total |  | 123,342 |  |  |  |  |
Accumulated Depreciation |  | $ 55,487 |  |  |  |  |
Depreciable Lives (Years) | [6] | (1) |  |  |  |  |
One and Two Reston Overlook | Boston Properties Limited Partnership | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 16,456 |  |  |  |  |
Original Building |  | 66,192 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 36,276 |  |  |  |  |
Land and Improvements |  | 15,074 |  |  |  |  |
Building and Improvements |  | 103,850 |  |  |  |  |
Total |  | 118,924 |  |  |  |  |
Accumulated Depreciation |  | $ 54,155 |  |  |  |  |
Depreciable Lives (Years) | [7] | (1) |  |  |  |  |
140 Kendrick Street | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 18,095 |  |  |  |  |
Original Building |  | 66,905 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 37,813 |  |  |  |  |
Land and Improvements |  | 19,092 |  |  |  |  |
Building and Improvements |  | 103,721 |  |  |  |  |
Total |  | 122,813 |  |  |  |  |
Accumulated Depreciation |  | $ 40,242 |  |  |  |  |
Depreciable Lives (Years) | [6] | (1) |  |  |  |  |
140 Kendrick Street | Boston Properties Limited Partnership | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 18,095 |  |  |  |  |
Original Building |  | 66,905 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 33,823 |  |  |  |  |
Land and Improvements |  | 18,095 |  |  |  |  |
Building and Improvements |  | 100,728 |  |  |  |  |
Total |  | 118,823 |  |  |  |  |
Accumulated Depreciation |  | $ 39,039 |  |  |  |  |
Depreciable Lives (Years) | [7] | (1) |  |  |  |  |
Shady Grove Innovation District [Member] | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 52,030 |  |  |  |  |
Original Building |  | 64,212 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 2,676 |  |  |  |  |
Land and Improvements |  | 26,834 |  |  |  |  |
Building and Improvements |  | 34,974 |  |  |  |  |
Land held for development |  | 57,110 |  |  |  |  |
Total |  | 118,918 |  |  |  |  |
Accumulated Depreciation |  | $ 1,048 |  |  |  |  |
Depreciable Lives (Years) | [6] | (1) |  |  |  |  |
Shady Grove Innovation District [Member] | Boston Properties Limited Partnership | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 52,030 |  |  |  |  |
Original Building |  | 64,212 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 2,676 |  |  |  |  |
Land and Improvements |  | 26,834 |  |  |  |  |
Building and Improvements |  | 34,974 |  |  |  |  |
Land held for development |  | 57,110 |  |  |  |  |
Total |  | 118,918 |  |  |  |  |
Accumulated Depreciation |  | $ 1,048 |  |  |  |  |
Depreciable Lives (Years) | [7] | (1) |  |  |  |  |
Weston Corporate Center | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 25,753 |  |  |  |  |
Original Building |  | 92,312 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 32 |  |  |  |  |
Land and Improvements |  | 25,854 |  |  |  |  |
Building and Improvements |  | 92,243 |  |  |  |  |
Total |  | 118,097 |  |  |  |  |
Accumulated Depreciation |  | $ 35,329 |  |  |  |  |
Depreciable Lives (Years) | [6] | (1) |  |  |  |  |
Weston Corporate Center | Boston Properties Limited Partnership | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 25,753 |  |  |  |  |
Original Building |  | 92,312 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 32 |  |  |  |  |
Land and Improvements |  | 25,854 |  |  |  |  |
Building and Improvements |  | 92,243 |  |  |  |  |
Total |  | 118,097 |  |  |  |  |
Accumulated Depreciation |  | $ 35,329 |  |  |  |  |
Depreciable Lives (Years) | [7] | (1) |  |  |  |  |
17Fifty Presidents Street | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 0 |  |  |  |  |
Original Building |  | 113,362 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 44 |  |  |  |  |
Land and Improvements |  | 0 |  |  |  |  |
Building and Improvements |  | 113,406 |  |  |  |  |
Total |  | 113,406 |  |  |  |  |
Accumulated Depreciation |  | $ 7,840 |  |  |  |  |
Depreciable Lives (Years) | [6] | (1) |  |  |  |  |
17Fifty Presidents Street | Boston Properties Limited Partnership | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 0 |  |  |  |  |
Original Building |  | 113,362 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 44 |  |  |  |  |
Land and Improvements |  | 0 |  |  |  |  |
Building and Improvements |  | 113,406 |  |  |  |  |
Total |  | 113,406 |  |  |  |  |
Accumulated Depreciation |  | $ 7,840 |  |  |  |  |
Depreciable Lives (Years) | [7] | (1) |  |  |  |  |
Discovery Square | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 11,198 |  |  |  |  |
Original Building |  | 71,782 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 21,304 |  |  |  |  |
Land and Improvements |  | 12,533 |  |  |  |  |
Building and Improvements |  | 91,751 |  |  |  |  |
Total |  | 104,284 |  |  |  |  |
Accumulated Depreciation |  | $ 50,358 |  |  |  |  |
Depreciable Lives (Years) | [6] | (1) |  |  |  |  |
Discovery Square | Boston Properties Limited Partnership | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 11,198 |  |  |  |  |
Original Building |  | 71,782 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 15,759 |  |  |  |  |
Land and Improvements |  | 11,146 |  |  |  |  |
Building and Improvements |  | 87,593 |  |  |  |  |
Total |  | 98,739 |  |  |  |  |
Accumulated Depreciation |  | $ 48,686 |  |  |  |  |
Depreciable Lives (Years) | [7] | (1) |  |  |  |  |
355 Main Street | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 18,863 |  |  |  |  |
Original Building |  | 53,346 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 24,995 |  |  |  |  |
Land and Improvements |  | 21,173 |  |  |  |  |
Building and Improvements |  | 76,031 |  |  |  |  |
Total |  | 97,204 |  |  |  |  |
Accumulated Depreciation |  | $ 31,827 |  |  |  |  |
Depreciable Lives (Years) | [6] | (1) |  |  |  |  |
355 Main Street | Boston Properties Limited Partnership | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 18,863 |  |  |  |  |
Original Building |  | 53,346 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 24,697 |  |  |  |  |
Land and Improvements |  | 21,098 |  |  |  |  |
Building and Improvements |  | 75,808 |  |  |  |  |
Total |  | 96,906 |  |  |  |  |
Accumulated Depreciation |  | $ 31,739 |  |  |  |  |
Depreciable Lives (Years) | [7] | (1) |  |  |  |  |
10 CityPoint | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 1,953 |  |  |  |  |
Original Building |  | 85,752 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 6,963 |  |  |  |  |
Land and Improvements |  | 2,290 |  |  |  |  |
Building and Improvements |  | 92,378 |  |  |  |  |
Total |  | 94,668 |  |  |  |  |
Accumulated Depreciation |  | $ 17,327 |  |  |  |  |
Depreciable Lives (Years) | [6] | (1) |  |  |  |  |
10 CityPoint | Boston Properties Limited Partnership | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 1,953 |  |  |  |  |
Original Building |  | 85,752 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 6,800 |  |  |  |  |
Land and Improvements |  | 2,127 |  |  |  |  |
Building and Improvements |  | 92,378 |  |  |  |  |
Total |  | 94,505 |  |  |  |  |
Accumulated Depreciation |  | $ 17,327 |  |  |  |  |
Depreciable Lives (Years) | [7] | (1) |  |  |  |  |
Two Freedom Square | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 13,930 |  |  |  |  |
Original Building |  | 77,739 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | (184) |  |  |  |  |
Land and Improvements |  | 15,420 |  |  |  |  |
Building and Improvements |  | 76,065 |  |  |  |  |
Total |  | 91,485 |  |  |  |  |
Accumulated Depreciation |  | $ 33,696 |  |  |  |  |
Depreciable Lives (Years) | [6] | (1) |  |  |  |  |
Two Freedom Square | Boston Properties Limited Partnership | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 13,930 |  |  |  |  |
Original Building |  | 77,739 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | (6,396) |  |  |  |  |
Land and Improvements |  | 13,866 |  |  |  |  |
Building and Improvements |  | 71,407 |  |  |  |  |
Total |  | 85,273 |  |  |  |  |
Accumulated Depreciation |  | $ 31,823 |  |  |  |  |
Depreciable Lives (Years) | [7] | (1) |  |  |  |  |
90 Broadway | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 19,104 |  |  |  |  |
Original Building |  | 52,078 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 18,876 |  |  |  |  |
Land and Improvements |  | 20,785 |  |  |  |  |
Building and Improvements |  | 69,273 |  |  |  |  |
Total |  | 90,058 |  |  |  |  |
Accumulated Depreciation |  | $ 26,797 |  |  |  |  |
Depreciable Lives (Years) | [6] | (1) |  |  |  |  |
90 Broadway | Boston Properties Limited Partnership | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 19,104 |  |  |  |  |
Original Building |  | 52,078 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 18,697 |  |  |  |  |
Land and Improvements |  | 20,741 |  |  |  |  |
Building and Improvements |  | 69,138 |  |  |  |  |
Total |  | 89,879 |  |  |  |  |
Accumulated Depreciation |  | $ 26,749 |  |  |  |  |
Depreciable Lives (Years) | [7] | (1) |  |  |  |  |
153 & 211 Second Avenue [Member] | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 33,233 |  |  |  |  |
Original Building |  | 55,940 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 0 |  |  |  |  |
Land and Improvements |  | 33,233 |  |  |  |  |
Building and Improvements |  | 55,940 |  |  |  |  |
Total |  | 89,173 |  |  |  |  |
Accumulated Depreciation |  | $ 1,819 |  |  |  |  |
Depreciable Lives (Years) | [6] | (1) |  |  |  |  |
153 & 211 Second Avenue [Member] | Boston Properties Limited Partnership | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 33,233 |  |  |  |  |
Original Building |  | 55,940 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 0 |  |  |  |  |
Land and Improvements |  | 33,233 |  |  |  |  |
Building and Improvements |  | 55,940 |  |  |  |  |
Total |  | 89,173 |  |  |  |  |
Accumulated Depreciation |  | $ 1,819 |  |  |  |  |
Depreciable Lives (Years) | [7] | (1) |  |  |  |  |
230 CityPoint | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 13,189 |  |  |  |  |
Original Building |  | 49,823 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 23,874 |  |  |  |  |
Land and Improvements |  | 13,807 |  |  |  |  |
Building and Improvements |  | 73,079 |  |  |  |  |
Total |  | 86,886 |  |  |  |  |
Accumulated Depreciation |  | $ 35,469 |  |  |  |  |
Depreciable Lives (Years) | [6] | (1) |  |  |  |  |
230 CityPoint | Boston Properties Limited Partnership | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 13,189 |  |  |  |  |
Original Building |  | 49,823 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 22,257 |  |  |  |  |
Land and Improvements |  | 13,403 |  |  |  |  |
Building and Improvements |  | 71,866 |  |  |  |  |
Total |  | 85,269 |  |  |  |  |
Accumulated Depreciation |  | $ 34,984 |  |  |  |  |
Depreciable Lives (Years) | [7] | (1) |  |  |  |  |
77 CityPoint | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 13,847 |  |  |  |  |
Original Building |  | 60,383 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 11,524 |  |  |  |  |
Land and Improvements |  | 14,023 |  |  |  |  |
Building and Improvements |  | 71,731 |  |  |  |  |
Total |  | 85,754 |  |  |  |  |
Accumulated Depreciation |  | $ 31,832 |  |  |  |  |
Depreciable Lives (Years) | [6] | (1) |  |  |  |  |
77 CityPoint | Boston Properties Limited Partnership | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 13,847 |  |  |  |  |
Original Building |  | 60,383 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 11,419 |  |  |  |  |
Land and Improvements |  | 13,997 |  |  |  |  |
Building and Improvements |  | 71,652 |  |  |  |  |
Total |  | 85,649 |  |  |  |  |
Accumulated Depreciation |  | $ 31,804 |  |  |  |  |
Depreciable Lives (Years) | [7] | (1) |  |  |  |  |
20 Citypoint | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 4,887 |  |  |  |  |
Original Building |  | 72,764 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 7,071 |  |  |  |  |
Land and Improvements |  | 4,887 |  |  |  |  |
Building and Improvements |  | 79,835 |  |  |  |  |
Total |  | 84,722 |  |  |  |  |
Accumulated Depreciation |  | $ 6,135 |  |  |  |  |
Depreciable Lives (Years) | [6] | (1) |  |  |  |  |
20 Citypoint | Boston Properties Limited Partnership | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 4,887 |  |  |  |  |
Original Building |  | 72,764 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 7,071 |  |  |  |  |
Land and Improvements |  | 4,887 |  |  |  |  |
Building and Improvements |  | 79,835 |  |  |  |  |
Total |  | 84,722 |  |  |  |  |
Accumulated Depreciation |  | $ 6,135 |  |  |  |  |
Depreciable Lives (Years) | [7] | (1) |  |  |  |  |
Waltham Weston Corporate Center | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 10,385 |  |  |  |  |
Original Building |  | 60,694 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 12,662 |  |  |  |  |
Land and Improvements |  | 11,097 |  |  |  |  |
Building and Improvements |  | 72,644 |  |  |  |  |
Total |  | 83,741 |  |  |  |  |
Accumulated Depreciation |  | $ 40,253 |  |  |  |  |
Depreciable Lives (Years) | [6] | (1) |  |  |  |  |
Waltham Weston Corporate Center | Boston Properties Limited Partnership | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 10,385 |  |  |  |  |
Original Building |  | 60,694 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 9,675 |  |  |  |  |
Land and Improvements |  | 10,350 |  |  |  |  |
Building and Improvements |  | 70,404 |  |  |  |  |
Total |  | 80,754 |  |  |  |  |
Accumulated Depreciation |  | $ 39,353 |  |  |  |  |
Depreciable Lives (Years) | [7] | (1) |  |  |  |  |
200 West Street | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 16,148 |  |  |  |  |
Original Building |  | 24,983 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 39,592 |  |  |  |  |
Land and Improvements |  | 16,813 |  |  |  |  |
Building and Improvements |  | 63,593 |  |  |  |  |
Land held for development |  | 317 |  |  |  |  |
Total |  | 80,723 |  |  |  |  |
Accumulated Depreciation |  | $ 19,724 |  |  |  |  |
Depreciable Lives (Years) | [6] | (1) |  |  |  |  |
200 West Street | Boston Properties Limited Partnership | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 16,148 |  |  |  |  |
Original Building |  | 24,983 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 36,931 |  |  |  |  |
Land and Improvements |  | 16,148 |  |  |  |  |
Building and Improvements |  | 61,597 |  |  |  |  |
Land held for development |  | 317 |  |  |  |  |
Total |  | 78,062 |  |  |  |  |
Accumulated Depreciation |  | $ 18,922 |  |  |  |  |
Depreciable Lives (Years) | [7] | (1) |  |  |  |  |
Sumner Square |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Right of use assets - operating leases |  |  |  | $ 27,100 |  |  |
Sumner Square | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 624 |  |  |  |  |
Original Building |  | 28,745 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 49,345 |  |  |  |  |
Land and Improvements |  | 28,548 |  |  |  |  |
Building and Improvements |  | 50,166 |  |  |  |  |
Total |  | 78,714 |  |  |  |  |
Accumulated Depreciation |  | $ 29,871 |  |  |  |  |
Depreciable Lives (Years) | [6] | (1) |  |  |  |  |
Sumner Square | Boston Properties Limited Partnership | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 624 |  |  |  |  |
Original Building |  | 28,745 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 47,265 |  |  |  |  |
Land and Improvements |  | 28,028 |  |  |  |  |
Building and Improvements |  | 48,606 |  |  |  |  |
Total |  | 76,634 |  |  |  |  |
Accumulated Depreciation |  | $ 29,247 |  |  |  |  |
Depreciable Lives (Years) | [7] | (1) |  |  |  |  |
2440 West El Camino Real | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 16,741 |  |  |  |  |
Original Building |  | 51,285 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 6,290 |  |  |  |  |
Land and Improvements |  | 16,741 |  |  |  |  |
Building and Improvements |  | 57,575 |  |  |  |  |
Total |  | 74,316 |  |  |  |  |
Accumulated Depreciation |  | $ 17,265 |  |  |  |  |
Depreciable Lives (Years) | [6] | (1) |  |  |  |  |
2440 West El Camino Real | Boston Properties Limited Partnership | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 16,741 |  |  |  |  |
Original Building |  | 51,285 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 6,290 |  |  |  |  |
Land and Improvements |  | 16,741 |  |  |  |  |
Building and Improvements |  | 57,575 |  |  |  |  |
Total |  | 74,316 |  |  |  |  |
Accumulated Depreciation |  | $ 17,265 |  |  |  |  |
Depreciable Lives (Years) | [7] | (1) |  |  |  |  |
300 Binney Street | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 18,080 |  |  |  |  |
Original Building |  | 51,262 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 140 |  |  |  |  |
Land and Improvements |  | 18,080 |  |  |  |  |
Building and Improvements |  | 51,402 |  |  |  |  |
Total |  | 69,482 |  |  |  |  |
Accumulated Depreciation |  | $ 14,537 |  |  |  |  |
Depreciable Lives (Years) | [6] | (1) |  |  |  |  |
300 Binney Street | Boston Properties Limited Partnership | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 18,080 |  |  |  |  |
Original Building |  | 51,262 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 140 |  |  |  |  |
Land and Improvements |  | 18,080 |  |  |  |  |
Building and Improvements |  | 51,402 |  |  |  |  |
Total |  | 69,482 |  |  |  |  |
Accumulated Depreciation |  | $ 14,537 |  |  |  |  |
Depreciable Lives (Years) | [7] | (1) |  |  |  |  |
Reston Corporate Center | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 9,135 |  |  |  |  |
Original Building |  | 50,857 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 6,236 |  |  |  |  |
Land and Improvements |  | 10,148 |  |  |  |  |
Building and Improvements |  | 56,080 |  |  |  |  |
Total |  | 66,228 |  |  |  |  |
Accumulated Depreciation |  | $ 32,950 |  |  |  |  |
Depreciable Lives (Years) | [6] | (1) |  |  |  |  |
Reston Corporate Center | Boston Properties Limited Partnership | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 9,135 |  |  |  |  |
Original Building |  | 50,857 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 3,625 |  |  |  |  |
Land and Improvements |  | 9,496 |  |  |  |  |
Building and Improvements |  | 54,121 |  |  |  |  |
Total |  | 63,617 |  |  |  |  |
Accumulated Depreciation |  | $ 32,162 |  |  |  |  |
Depreciable Lives (Years) | [7] | (1) |  |  |  |  |
Wisconsin Place | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 0 |  |  |  |  |
Original Building |  | 53,349 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 12,600 |  |  |  |  |
Land and Improvements |  | 0 |  |  |  |  |
Building and Improvements |  | 65,949 |  |  |  |  |
Total |  | 65,949 |  |  |  |  |
Accumulated Depreciation |  | $ 28,025 |  |  |  |  |
Depreciable Lives (Years) | [6] | (1) |  |  |  |  |
Wisconsin Place | Boston Properties Limited Partnership | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 0 |  |  |  |  |
Original Building |  | 53,349 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 12,600 |  |  |  |  |
Land and Improvements |  | 0 |  |  |  |  |
Building and Improvements |  | 65,949 |  |  |  |  |
Total |  | 65,949 |  |  |  |  |
Accumulated Depreciation |  | $ 28,025 |  |  |  |  |
Depreciable Lives (Years) | [7] | (1) |  |  |  |  |
255 Main Street | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 134 |  |  |  |  |
Original Building |  | 25,110 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 34,260 |  |  |  |  |
Land and Improvements |  | 548 |  |  |  |  |
Building and Improvements |  | 58,956 |  |  |  |  |
Total |  | 59,504 |  |  |  |  |
Accumulated Depreciation |  | $ 39,791 |  |  |  |  |
Depreciable Lives (Years) | [6] | (1) |  |  |  |  |
255 Main Street | Boston Properties Limited Partnership | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 134 |  |  |  |  |
Original Building |  | 25,110 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 32,604 |  |  |  |  |
Land and Improvements |  | 134 |  |  |  |  |
Building and Improvements |  | 57,714 |  |  |  |  |
Total |  | 57,848 |  |  |  |  |
Accumulated Depreciation |  | $ 39,294 |  |  |  |  |
Depreciable Lives (Years) | [7] | (1) |  |  |  |  |
University Place | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 0 |  |  |  |  |
Original Building |  | 37,091 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 16,512 |  |  |  |  |
Land and Improvements |  | 6,004 |  |  |  |  |
Building and Improvements |  | 47,599 |  |  |  |  |
Total |  | 53,603 |  |  |  |  |
Accumulated Depreciation |  | $ 33,469 |  |  |  |  |
Depreciable Lives (Years) | [6] | (1) |  |  |  |  |
University Place | Boston Properties Limited Partnership | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 0 |  |  |  |  |
Original Building |  | 37,091 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 15,062 |  |  |  |  |
Land and Improvements |  | 6,004 |  |  |  |  |
Building and Improvements |  | 46,149 |  |  |  |  |
Total |  | 52,153 |  |  |  |  |
Accumulated Depreciation |  | $ 32,504 |  |  |  |  |
Depreciable Lives (Years) | [7] | (1) |  |  |  |  |
890 Winter Street | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 13,913 |  |  |  |  |
Original Building |  | 28,557 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 4,745 |  |  |  |  |
Land and Improvements |  | 13,913 |  |  |  |  |
Building and Improvements |  | 33,302 |  |  |  |  |
Total |  | 47,215 |  |  |  |  |
Accumulated Depreciation |  | $ 3,928 |  |  |  |  |
Depreciable Lives (Years) | [6] | (1) |  |  |  |  |
890 Winter Street | Boston Properties Limited Partnership | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 13,913 |  |  |  |  |
Original Building |  | 28,557 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 4,745 |  |  |  |  |
Land and Improvements |  | 13,913 |  |  |  |  |
Building and Improvements |  | 33,302 |  |  |  |  |
Total |  | 47,215 |  |  |  |  |
Accumulated Depreciation |  | $ 3,928 |  |  |  |  |
Depreciable Lives (Years) | [7] | (1) |  |  |  |  |
Capital Gallery | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 4,725 |  |  |  |  |
Original Building |  | 29,565 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 9,681 |  |  |  |  |
Land and Improvements |  | 8,662 |  |  |  |  |
Building and Improvements |  | 35,309 |  |  |  |  |
Total |  | 43,971 |  |  |  |  |
Accumulated Depreciation |  | $ 21,562 |  |  |  |  |
Depreciable Lives (Years) | [6] | (1) |  |  |  |  |
Capital Gallery | Boston Properties Limited Partnership | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 4,725 |  |  |  |  |
Original Building |  | 29,565 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 5,018 |  |  |  |  |
Land and Improvements |  | 6,128 |  |  |  |  |
Building and Improvements |  | 33,180 |  |  |  |  |
Total |  | 39,308 |  |  |  |  |
Accumulated Depreciation |  | $ 20,706 |  |  |  |  |
Depreciable Lives (Years) | [7] | (1) |  |  |  |  |
North First Business Park | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 23,398 |  |  |  |  |
Original Building |  | 13,069 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 4,545 |  |  |  |  |
Land and Improvements |  | 23,377 |  |  |  |  |
Building and Improvements |  | 17,635 |  |  |  |  |
Total |  | 41,012 |  |  |  |  |
Accumulated Depreciation |  | $ 17,017 |  |  |  |  |
Depreciable Lives (Years) | [6] | (1) |  |  |  |  |
North First Business Park | Boston Properties Limited Partnership | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 23,398 |  |  |  |  |
Original Building |  | 13,069 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 4,522 |  |  |  |  |
Land and Improvements |  | 23,371 |  |  |  |  |
Building and Improvements |  | 17,618 |  |  |  |  |
Total |  | 40,989 |  |  |  |  |
Accumulated Depreciation |  | $ 17,011 |  |  |  |  |
Depreciable Lives (Years) | [7] | (1) |  |  |  |  |
150 Broadway | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 850 |  |  |  |  |
Original Building |  | 25,042 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 2,350 |  |  |  |  |
Land and Improvements |  | 1,323 |  |  |  |  |
Building and Improvements |  | 26,919 |  |  |  |  |
Total |  | 28,242 |  |  |  |  |
Accumulated Depreciation |  | $ 14,833 |  |  |  |  |
Depreciable Lives (Years) | [6] | (1) |  |  |  |  |
150 Broadway | Boston Properties Limited Partnership | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 850 |  |  |  |  |
Original Building |  | 25,042 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 345 |  |  |  |  |
Land and Improvements |  | 822 |  |  |  |  |
Building and Improvements |  | 25,415 |  |  |  |  |
Total |  | 26,237 |  |  |  |  |
Accumulated Depreciation |  | $ 14,225 |  |  |  |  |
Depreciable Lives (Years) | [7] | (1) |  |  |  |  |
105 Broadway | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 1,299 |  |  |  |  |
Original Building |  | 12,943 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 12,723 |  |  |  |  |
Land and Improvements |  | 2,395 |  |  |  |  |
Building and Improvements |  | 24,570 |  |  |  |  |
Total |  | 26,965 |  |  |  |  |
Accumulated Depreciation |  | $ 14,309 |  |  |  |  |
Depreciable Lives (Years) | [6] | (1) |  |  |  |  |
105 Broadway | Boston Properties Limited Partnership | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 1,299 |  |  |  |  |
Original Building |  | 12,943 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 10,617 |  |  |  |  |
Land and Improvements |  | 1,868 |  |  |  |  |
Building and Improvements |  | 22,991 |  |  |  |  |
Total |  | 24,859 |  |  |  |  |
Accumulated Depreciation |  | $ 13,674 |  |  |  |  |
Depreciable Lives (Years) | [7] | (1) |  |  |  |  |
Lexington Office Park | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 998 |  |  |  |  |
Original Building |  | 1,426 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 18,582 |  |  |  |  |
Land and Improvements |  | 1,264 |  |  |  |  |
Building and Improvements |  | 19,551 |  |  |  |  |
Land held for development |  | 191 |  |  |  |  |
Total |  | 21,006 |  |  |  |  |
Accumulated Depreciation |  | $ 16,012 |  |  |  |  |
Depreciable Lives (Years) | [6] | (1) |  |  |  |  |
Lexington Office Park | Boston Properties Limited Partnership | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 998 |  |  |  |  |
Original Building |  | 1,426 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 17,818 |  |  |  |  |
Land and Improvements |  | 1,073 |  |  |  |  |
Building and Improvements |  | 18,978 |  |  |  |  |
Land held for development |  | 191 |  |  |  |  |
Total |  | 20,242 |  |  |  |  |
Accumulated Depreciation |  | $ 15,785 |  |  |  |  |
Depreciable Lives (Years) | [7] | (1) |  |  |  |  |
The Point | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 6,395 |  |  |  |  |
Original Building |  | 10,040 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 421 |  |  |  |  |
Land and Improvements |  | 6,492 |  |  |  |  |
Building and Improvements |  | 10,364 |  |  |  |  |
Total |  | 16,856 |  |  |  |  |
Accumulated Depreciation |  | $ 1,984 |  |  |  |  |
Depreciable Lives (Years) | [6] | (1) |  |  |  |  |
The Point | Boston Properties Limited Partnership | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 6,395 |  |  |  |  |
Original Building |  | 10,040 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 421 |  |  |  |  |
Land and Improvements |  | 6,492 |  |  |  |  |
Building and Improvements |  | 10,364 |  |  |  |  |
Total |  | 16,856 |  |  |  |  |
Accumulated Depreciation |  | $ 1,984 |  |  |  |  |
Depreciable Lives (Years) | [7] | (1) |  |  |  |  |
690 Folsom Street | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 3,219 |  |  |  |  |
Original Building |  | 11,038 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 1,877 |  |  |  |  |
Land and Improvements |  | 3,219 |  |  |  |  |
Building and Improvements |  | 12,915 |  |  |  |  |
Total |  | 16,134 |  |  |  |  |
Accumulated Depreciation |  | $ 3,354 |  |  |  |  |
Depreciable Lives (Years) | [6] | (1) |  |  |  |  |
690 Folsom Street | Boston Properties Limited Partnership | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 3,219 |  |  |  |  |
Original Building |  | 11,038 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 1,877 |  |  |  |  |
Land and Improvements |  | 3,219 |  |  |  |  |
Building and Improvements |  | 12,915 |  |  |  |  |
Total |  | 16,134 |  |  |  |  |
Accumulated Depreciation |  | $ 3,354 |  |  |  |  |
Depreciable Lives (Years) | [7] | (1) |  |  |  |  |
195 West Street | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 1,611 |  |  |  |  |
Original Building |  | 6,652 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 7,470 |  |  |  |  |
Land and Improvements |  | 1,858 |  |  |  |  |
Building and Improvements |  | 13,875 |  |  |  |  |
Total |  | 15,733 |  |  |  |  |
Accumulated Depreciation |  | $ 8,842 |  |  |  |  |
Depreciable Lives (Years) | [6] | (1) |  |  |  |  |
195 West Street | Boston Properties Limited Partnership | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 1,611 |  |  |  |  |
Original Building |  | 6,652 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 6,481 |  |  |  |  |
Land and Improvements |  | 1,611 |  |  |  |  |
Building and Improvements |  | 13,133 |  |  |  |  |
Total |  | 14,744 |  |  |  |  |
Accumulated Depreciation |  | $ 8,540 |  |  |  |  |
Depreciable Lives (Years) | [7] | (1) |  |  |  |  |
33 Hayden Avenue | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 266 |  |  |  |  |
Original Building |  | 3,234 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 11,501 |  |  |  |  |
Land and Improvements |  | 425 |  |  |  |  |
Building and Improvements |  | 14,576 |  |  |  |  |
Total |  | 15,001 |  |  |  |  |
Accumulated Depreciation |  | $ 6,768 |  |  |  |  |
Depreciable Lives (Years) | [6] | (1) |  |  |  |  |
33 Hayden Avenue | Boston Properties Limited Partnership | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 266 |  |  |  |  |
Original Building |  | 3,234 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 10,864 |  |  |  |  |
Land and Improvements |  | 266 |  |  |  |  |
Building and Improvements |  | 14,098 |  |  |  |  |
Total |  | 14,364 |  |  |  |  |
Accumulated Depreciation |  | $ 6,576 |  |  |  |  |
Depreciable Lives (Years) | [7] | (1) |  |  |  |  |
92-100 Hayden Avenue | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 594 |  |  |  |  |
Original Building |  | 6,748 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 6,259 |  |  |  |  |
Land and Improvements |  | 802 |  |  |  |  |
Building and Improvements |  | 12,799 |  |  |  |  |
Total |  | 13,601 |  |  |  |  |
Accumulated Depreciation |  | $ 11,468 |  |  |  |  |
Depreciable Lives (Years) | [6] | (1) |  |  |  |  |
92-100 Hayden Avenue | Boston Properties Limited Partnership | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 594 |  |  |  |  |
Original Building |  | 6,748 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 5,530 |  |  |  |  |
Land and Improvements |  | 619 |  |  |  |  |
Building and Improvements |  | 12,253 |  |  |  |  |
Total |  | 12,872 |  |  |  |  |
Accumulated Depreciation |  | $ 11,247 |  |  |  |  |
Depreciable Lives (Years) | [7] | (1) |  |  |  |  |
7501 Boston Boulevard, Building Seven | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 665 |  |  |  |  |
Original Building |  | 9,273 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 819 |  |  |  |  |
Land and Improvements |  | 791 |  |  |  |  |
Building and Improvements |  | 9,966 |  |  |  |  |
Total |  | 10,757 |  |  |  |  |
Accumulated Depreciation |  | $ 5,937 |  |  |  |  |
Depreciable Lives (Years) | [6] | (1) |  |  |  |  |
7501 Boston Boulevard, Building Seven | Boston Properties Limited Partnership | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 665 |  |  |  |  |
Original Building |  | 9,273 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 314 |  |  |  |  |
Land and Improvements |  | 665 |  |  |  |  |
Building and Improvements |  | 9,587 |  |  |  |  |
Total |  | 10,252 |  |  |  |  |
Accumulated Depreciation |  | $ 5,783 |  |  |  |  |
Depreciable Lives (Years) | [7] | (1) |  |  |  |  |
7435 Boston Boulevard, Building One | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 392 |  |  |  |  |
Original Building |  | 3,822 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 5,016 |  |  |  |  |
Land and Improvements |  | 659 |  |  |  |  |
Building and Improvements |  | 8,571 |  |  |  |  |
Total |  | 9,230 |  |  |  |  |
Accumulated Depreciation |  | $ 7,010 |  |  |  |  |
Depreciable Lives (Years) | [6] | (1) |  |  |  |  |
7435 Boston Boulevard, Building One | Boston Properties Limited Partnership | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 392 |  |  |  |  |
Original Building |  | 3,822 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 4,323 |  |  |  |  |
Land and Improvements |  | 486 |  |  |  |  |
Building and Improvements |  | 8,051 |  |  |  |  |
Total |  | 8,537 |  |  |  |  |
Accumulated Depreciation |  | $ 6,802 |  |  |  |  |
Depreciable Lives (Years) | [7] | (1) |  |  |  |  |
32 Hartwell Avenue | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 168 |  |  |  |  |
Original Building |  | 1,943 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 6,944 |  |  |  |  |
Land and Improvements |  | 314 |  |  |  |  |
Building and Improvements |  | 8,741 |  |  |  |  |
Total |  | 9,055 |  |  |  |  |
Accumulated Depreciation |  | $ 2,734 |  |  |  |  |
Depreciable Lives (Years) | [6] | (1) |  |  |  |  |
32 Hartwell Avenue | Boston Properties Limited Partnership | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 168 |  |  |  |  |
Original Building |  | 1,943 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 6,358 |  |  |  |  |
Land and Improvements |  | 168 |  |  |  |  |
Building and Improvements |  | 8,301 |  |  |  |  |
Total |  | 8,469 |  |  |  |  |
Accumulated Depreciation |  | $ 2,557 |  |  |  |  |
Depreciable Lives (Years) | [7] | (1) |  |  |  |  |
7450 Boston Boulevard, Building Three | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 1,165 |  |  |  |  |
Original Building |  | 4,681 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 2,613 |  |  |  |  |
Land and Improvements |  | 1,430 |  |  |  |  |
Building and Improvements |  | 7,029 |  |  |  |  |
Total |  | 8,459 |  |  |  |  |
Accumulated Depreciation |  | $ 4,774 |  |  |  |  |
Depreciable Lives (Years) | [6] | (1) |  |  |  |  |
7450 Boston Boulevard, Building Three | Boston Properties Limited Partnership | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 1,165 |  |  |  |  |
Original Building |  | 4,681 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 2,199 |  |  |  |  |
Land and Improvements |  | 1,327 |  |  |  |  |
Building and Improvements |  | 6,718 |  |  |  |  |
Total |  | 8,045 |  |  |  |  |
Accumulated Depreciation |  | $ 4,646 |  |  |  |  |
Depreciable Lives (Years) | [7] | (1) |  |  |  |  |
250 Binney Street | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 110 |  |  |  |  |
Original Building |  | 4,483 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 3,593 |  |  |  |  |
Land and Improvements |  | 273 |  |  |  |  |
Building and Improvements |  | 7,913 |  |  |  |  |
Total |  | 8,186 |  |  |  |  |
Accumulated Depreciation |  | $ 6,593 |  |  |  |  |
Depreciable Lives (Years) | [6] | (1) |  |  |  |  |
250 Binney Street | Boston Properties Limited Partnership | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 110 |  |  |  |  |
Original Building |  | 4,483 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 2,939 |  |  |  |  |
Land and Improvements |  | 110 |  |  |  |  |
Building and Improvements |  | 7,422 |  |  |  |  |
Total |  | 7,532 |  |  |  |  |
Accumulated Depreciation |  | $ 6,399 |  |  |  |  |
Depreciable Lives (Years) | [7] | (1) |  |  |  |  |
8000 Grainger Court Building Five | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 366 |  |  |  |  |
Original Building |  | 4,282 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 3,198 |  |  |  |  |
Land and Improvements |  | 601 |  |  |  |  |
Building and Improvements |  | 7,245 |  |  |  |  |
Total |  | 7,846 |  |  |  |  |
Accumulated Depreciation |  | $ 6,093 |  |  |  |  |
Depreciable Lives (Years) | [6] | (1) |  |  |  |  |
8000 Grainger Court Building Five | Boston Properties Limited Partnership | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 366 |  |  |  |  |
Original Building |  | 4,282 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 2,604 |  |  |  |  |
Land and Improvements |  | 453 |  |  |  |  |
Building and Improvements |  | 6,799 |  |  |  |  |
Total |  | 7,252 |  |  |  |  |
Accumulated Depreciation |  | $ 5,916 |  |  |  |  |
Depreciable Lives (Years) | [7] | (1) |  |  |  |  |
453 Ravendale Drive | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 5,477 |  |  |  |  |
Original Building |  | 1,090 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 676 |  |  |  |  |
Land and Improvements |  | 5,477 |  |  |  |  |
Building and Improvements |  | 1,766 |  |  |  |  |
Total |  | 7,243 |  |  |  |  |
Accumulated Depreciation |  | $ 924 |  |  |  |  |
Depreciable Lives (Years) | [6] | (1) |  |  |  |  |
453 Ravendale Drive | Boston Properties Limited Partnership | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 5,477 |  |  |  |  |
Original Building |  | 1,090 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 676 |  |  |  |  |
Land and Improvements |  | 5,477 |  |  |  |  |
Building and Improvements |  | 1,766 |  |  |  |  |
Total |  | 7,243 |  |  |  |  |
Accumulated Depreciation |  | $ 924 |  |  |  |  |
Depreciable Lives (Years) | [7] | (1) |  |  |  |  |
7300 Boston Boulevard Building Thirteen | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 608 |  |  |  |  |
Original Building |  | 4,773 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 1,075 |  |  |  |  |
Land and Improvements |  | 661 |  |  |  |  |
Building and Improvements |  | 5,795 |  |  |  |  |
Total |  | 6,456 |  |  |  |  |
Accumulated Depreciation |  | $ 2,527 |  |  |  |  |
Depreciable Lives (Years) | [6] | (1) |  |  |  |  |
7300 Boston Boulevard Building Thirteen | Boston Properties Limited Partnership | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 608 |  |  |  |  |
Original Building |  | 4,773 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 863 |  |  |  |  |
Land and Improvements |  | 608 |  |  |  |  |
Building and Improvements |  | 5,636 |  |  |  |  |
Total |  | 6,244 |  |  |  |  |
Accumulated Depreciation |  | $ 2,463 |  |  |  |  |
Depreciable Lives (Years) | [7] | (1) |  |  |  |  |
17 Hartwell Avenue | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 26 |  |  |  |  |
Original Building |  | 150 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 6,078 |  |  |  |  |
Land and Improvements |  | 65 |  |  |  |  |
Building and Improvements |  | 6,189 |  |  |  |  |
Total |  | 6,254 |  |  |  |  |
Accumulated Depreciation |  | $ 3,009 |  |  |  |  |
Depreciable Lives (Years) | [6] | (1) |  |  |  |  |
17 Hartwell Avenue | Boston Properties Limited Partnership | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 26 |  |  |  |  |
Original Building |  | 150 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 5,921 |  |  |  |  |
Land and Improvements |  | 26 |  |  |  |  |
Building and Improvements |  | 6,071 |  |  |  |  |
Total |  | 6,097 |  |  |  |  |
Accumulated Depreciation |  | $ 2,961 |  |  |  |  |
Depreciable Lives (Years) | [7] | (1) |  |  |  |  |
7601 Boston Boulevard Building Eight | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 200 |  |  |  |  |
Original Building |  | 878 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 5,045 |  |  |  |  |
Land and Improvements |  | 551 |  |  |  |  |
Building and Improvements |  | 5,572 |  |  |  |  |
Total |  | 6,123 |  |  |  |  |
Accumulated Depreciation |  | $ 4,986 |  |  |  |  |
Depreciable Lives (Years) | [6] | (1) |  |  |  |  |
7601 Boston Boulevard Building Eight | Boston Properties Limited Partnership | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 200 |  |  |  |  |
Original Building |  | 878 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 4,352 |  |  |  |  |
Land and Improvements |  | 378 |  |  |  |  |
Building and Improvements |  | 5,052 |  |  |  |  |
Total |  | 5,430 |  |  |  |  |
Accumulated Depreciation |  | $ 4,778 |  |  |  |  |
Depreciable Lives (Years) | [7] | (1) |  |  |  |  |
7500 Boston Boulevard Building Six | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 138 |  |  |  |  |
Original Building |  | 3,749 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 1,714 |  |  |  |  |
Land and Improvements |  | 367 |  |  |  |  |
Building and Improvements |  | 5,234 |  |  |  |  |
Total |  | 5,601 |  |  |  |  |
Accumulated Depreciation |  | $ 4,536 |  |  |  |  |
Depreciable Lives (Years) | [6] | (1) |  |  |  |  |
7500 Boston Boulevard Building Six | Boston Properties Limited Partnership | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 138 |  |  |  |  |
Original Building |  | 3,749 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 1,181 |  |  |  |  |
Land and Improvements |  | 234 |  |  |  |  |
Building and Improvements |  | 4,834 |  |  |  |  |
Total |  | 5,068 |  |  |  |  |
Accumulated Depreciation |  | $ 4,376 |  |  |  |  |
Depreciable Lives (Years) | [7] | (1) |  |  |  |  |
8000 Corporate Court Building Eleven | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 136 |  |  |  |  |
Original Building |  | 3,071 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 1,903 |  |  |  |  |
Land and Improvements |  | 774 |  |  |  |  |
Building and Improvements |  | 4,336 |  |  |  |  |
Total |  | 5,110 |  |  |  |  |
Accumulated Depreciation |  | $ 3,455 |  |  |  |  |
Depreciable Lives (Years) | [6] | (1) |  |  |  |  |
8000 Corporate Court Building Eleven | Boston Properties Limited Partnership | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 136 |  |  |  |  |
Original Building |  | 3,071 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 1,552 |  |  |  |  |
Land and Improvements |  | 686 |  |  |  |  |
Building and Improvements |  | 4,073 |  |  |  |  |
Total |  | 4,759 |  |  |  |  |
Accumulated Depreciation |  | $ 3,346 |  |  |  |  |
Depreciable Lives (Years) | [7] | (1) |  |  |  |  |
7375 Boston Boulevard Building Ten | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 23 |  |  |  |  |
Original Building |  | 2,685 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 1,005 |  |  |  |  |
Land and Improvements |  | 93 |  |  |  |  |
Building and Improvements |  | 3,620 |  |  |  |  |
Total |  | 3,713 |  |  |  |  |
Accumulated Depreciation |  | $ 2,841 |  |  |  |  |
Depreciable Lives (Years) | [6] | (1) |  |  |  |  |
7375 Boston Boulevard Building Ten | Boston Properties Limited Partnership | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 23 |  |  |  |  |
Original Building |  | 2,685 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 824 |  |  |  |  |
Land and Improvements |  | 47 |  |  |  |  |
Building and Improvements |  | 3,485 |  |  |  |  |
Total |  | 3,532 |  |  |  |  |
Accumulated Depreciation |  | $ 2,790 |  |  |  |  |
Depreciable Lives (Years) | [7] | (1) |  |  |  |  |
7451 Boston Boulevard Building Two | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 249 |  |  |  |  |
Original Building |  | 1,542 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 1,858 |  |  |  |  |
Land and Improvements |  | 613 |  |  |  |  |
Building and Improvements |  | 3,036 |  |  |  |  |
Total |  | 3,649 |  |  |  |  |
Accumulated Depreciation |  | $ 2,806 |  |  |  |  |
Depreciable Lives (Years) | [6] | (1) |  |  |  |  |
7451 Boston Boulevard Building Two | Boston Properties Limited Partnership | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 249 |  |  |  |  |
Original Building |  | 1,542 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 1,545 |  |  |  |  |
Land and Improvements |  | 535 |  |  |  |  |
Building and Improvements |  | 2,801 |  |  |  |  |
Total |  | 3,336 |  |  |  |  |
Accumulated Depreciation |  | $ 2,711 |  |  |  |  |
Depreciable Lives (Years) | [7] | (1) |  |  |  |  |
7374 Boston Boulevard Building Four | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 241 |  |  |  |  |
Original Building |  | 1,605 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 1,664 |  |  |  |  |
Land and Improvements |  | 398 |  |  |  |  |
Building and Improvements |  | 3,112 |  |  |  |  |
Total |  | 3,510 |  |  |  |  |
Accumulated Depreciation |  | $ 2,787 |  |  |  |  |
Depreciable Lives (Years) | [6] | (1) |  |  |  |  |
7374 Boston Boulevard Building Four | Boston Properties Limited Partnership | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 241 |  |  |  |  |
Original Building |  | 1,605 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 1,281 |  |  |  |  |
Land and Improvements |  | 303 |  |  |  |  |
Building and Improvements |  | 2,824 |  |  |  |  |
Total |  | 3,127 |  |  |  |  |
Accumulated Depreciation |  | $ 2,675 |  |  |  |  |
Depreciable Lives (Years) | [7] | (1) |  |  |  |  |
The Skylyne | Residential Building |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 28,962 |  |  |  |  |
Original Building |  | 239,077 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 1,097 |  |  |  |  |
Land and Improvements |  | 28,962 |  |  |  |  |
Building and Improvements |  | 240,174 |  |  |  |  |
Total |  | 269,136 |  |  |  |  |
Accumulated Depreciation |  | $ 8,132 |  |  |  |  |
Depreciable Lives (Years) | [6] | (1) |  |  |  |  |
The Skylyne | Boston Properties Limited Partnership | Residential Building |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 28,962 |  |  |  |  |
Original Building |  | 239,077 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 1,097 |  |  |  |  |
Land and Improvements |  | 28,962 |  |  |  |  |
Building and Improvements |  | 240,174 |  |  |  |  |
Total |  | 269,136 |  |  |  |  |
Accumulated Depreciation |  | $ 8,132 |  |  |  |  |
Depreciable Lives (Years) | [7] | (1) |  |  |  |  |
Signature at Reston | Residential Building |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 27,076 |  |  |  |  |
Original Building |  | 190,580 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 838 |  |  |  |  |
Land and Improvements |  | 27,076 |  |  |  |  |
Building and Improvements |  | 191,418 |  |  |  |  |
Total |  | 218,494 |  |  |  |  |
Accumulated Depreciation |  | $ 18,534 |  |  |  |  |
Depreciable Lives (Years) | [6] | (1) |  |  |  |  |
Signature at Reston | Boston Properties Limited Partnership | Residential Building |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 27,076 |  |  |  |  |
Original Building |  | 190,580 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 838 |  |  |  |  |
Land and Improvements |  | 27,076 |  |  |  |  |
Building and Improvements |  | 191,418 |  |  |  |  |
Total |  | 218,494 |  |  |  |  |
Accumulated Depreciation |  | $ 18,534 |  |  |  |  |
Depreciable Lives (Years) | [7] | (1) |  |  |  |  |
Proto Kendall Square | Residential Building |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 9,243 |  |  |  |  |
Original Building |  | 127,248 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 3,336 |  |  |  |  |
Land and Improvements |  | 9,245 |  |  |  |  |
Building and Improvements |  | 130,582 |  |  |  |  |
Total |  | 139,827 |  |  |  |  |
Accumulated Depreciation |  | $ 11,195 |  |  |  |  |
Depreciable Lives (Years) | [6] | (1) |  |  |  |  |
Proto Kendall Square | Boston Properties Limited Partnership | Residential Building |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 9,243 |  |  |  |  |
Original Building |  | 127,248 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 3,336 |  |  |  |  |
Land and Improvements |  | 9,245 |  |  |  |  |
Building and Improvements |  | 130,582 |  |  |  |  |
Total |  | 139,827 |  |  |  |  |
Accumulated Depreciation |  | $ 11,195 |  |  |  |  |
Depreciable Lives (Years) | [7] | (1) |  |  |  |  |
The Avant at Reston Town Center | Residential Building |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 20,350 |  |  |  |  |
Original Building |  | 91,995 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 846 |  |  |  |  |
Land and Improvements |  | 20,350 |  |  |  |  |
Building and Improvements |  | 92,841 |  |  |  |  |
Total |  | 113,191 |  |  |  |  |
Accumulated Depreciation |  | $ 19,681 |  |  |  |  |
Depreciable Lives (Years) | [6] | (1) |  |  |  |  |
The Avant at Reston Town Center | Boston Properties Limited Partnership | Residential Building |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 20,350 |  |  |  |  |
Original Building |  | 91,995 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 846 |  |  |  |  |
Land and Improvements |  | 20,350 |  |  |  |  |
Building and Improvements |  | 92,841 |  |  |  |  |
Total |  | 113,191 |  |  |  |  |
Accumulated Depreciation |  | $ 19,681 |  |  |  |  |
Depreciable Lives (Years) | [7] | (1) |  |  |  |  |
The Lofts at Atlantic Wharf | Residential Building |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 3,529 |  |  |  |  |
Original Building |  | 54,891 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 2,215 |  |  |  |  |
Land and Improvements |  | 3,529 |  |  |  |  |
Building and Improvements |  | 57,106 |  |  |  |  |
Total |  | 60,635 |  |  |  |  |
Accumulated Depreciation |  | $ 15,689 |  |  |  |  |
Depreciable Lives (Years) | [6] | (1) |  |  |  |  |
The Lofts at Atlantic Wharf | Boston Properties Limited Partnership | Residential Building |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 3,529 |  |  |  |  |
Original Building |  | 54,891 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 2,215 |  |  |  |  |
Land and Improvements |  | 3,529 |  |  |  |  |
Building and Improvements |  | 57,106 |  |  |  |  |
Total |  | 60,635 |  |  |  |  |
Accumulated Depreciation |  | $ 15,689 |  |  |  |  |
Depreciable Lives (Years) | [7] | (1) |  |  |  |  |
Boston Cambridge Marriott | Hotel [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 478 |  |  |  |  |
Original Building |  | 37,918 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 35,117 |  |  |  |  |
Land and Improvements |  | 1,201 |  |  |  |  |
Building and Improvements |  | 72,312 |  |  |  |  |
Total |  | 73,513 |  |  |  |  |
Accumulated Depreciation |  | $ 51,600 |  |  |  |  |
Depreciable Lives (Years) | [6] | (1) |  |  |  |  |
Boston Cambridge Marriott | Boston Properties Limited Partnership | Hotel [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 478 |  |  |  |  |
Original Building |  | 37,918 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 32,226 |  |  |  |  |
Land and Improvements |  | 478 |  |  |  |  |
Building and Improvements |  | 70,144 |  |  |  |  |
Total |  | 70,622 |  |  |  |  |
Accumulated Depreciation |  | $ 50,729 |  |  |  |  |
Depreciable Lives (Years) | [7] | (1) |  |  |  |  |
Kendall Center Green Garage | Garage |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 0 |  |  |  |  |
Original Building |  | 35,035 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 6,846 |  |  |  |  |
Land and Improvements |  | 103 |  |  |  |  |
Building and Improvements |  | 41,778 |  |  |  |  |
Total |  | 41,881 |  |  |  |  |
Accumulated Depreciation |  | $ 15,818 |  |  |  |  |
Depreciable Lives (Years) | [6] | (1) |  |  |  |  |
Kendall Center Green Garage | Boston Properties Limited Partnership | Garage |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 0 |  |  |  |  |
Original Building |  | 35,035 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 6,432 |  |  |  |  |
Land and Improvements |  | 0 |  |  |  |  |
Building and Improvements |  | 41,467 |  |  |  |  |
Total |  | 41,467 |  |  |  |  |
Accumulated Depreciation |  | $ 15,695 |  |  |  |  |
Depreciable Lives (Years) | [7] | (1) |  |  |  |  |
Kendall Center Yellow Garage | Garage |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 1,256 |  |  |  |  |
Original Building |  | 15,697 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 1,552 |  |  |  |  |
Land and Improvements |  | 1,434 |  |  |  |  |
Building and Improvements |  | 17,071 |  |  |  |  |
Total |  | 18,505 |  |  |  |  |
Accumulated Depreciation |  | $ 6,939 |  |  |  |  |
Depreciable Lives (Years) | [6] | (1) |  |  |  |  |
Kendall Center Yellow Garage | Boston Properties Limited Partnership | Garage |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 1,256 |  |  |  |  |
Original Building |  | 15,697 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 840 |  |  |  |  |
Land and Improvements |  | 1,256 |  |  |  |  |
Building and Improvements |  | 16,537 |  |  |  |  |
Total |  | 17,793 |  |  |  |  |
Accumulated Depreciation |  | $ 6,727 |  |  |  |  |
Depreciable Lives (Years) | [7] | (1) |  |  |  |  |
Kendall Center Blue Garage | Garage |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 1,163 |  |  |  |  |
Original Building |  | 11,633 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 2,111 |  |  |  |  |
Land and Improvements |  | 1,579 |  |  |  |  |
Building and Improvements |  | 13,328 |  |  |  |  |
Total |  | 14,907 |  |  |  |  |
Accumulated Depreciation |  | $ 10,399 |  |  |  |  |
Depreciable Lives (Years) | [6] | (1) |  |  |  |  |
Kendall Center Blue Garage | Boston Properties Limited Partnership | Garage |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 1,163 |  |  |  |  |
Original Building |  | 11,633 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 446 |  |  |  |  |
Land and Improvements |  | 1,163 |  |  |  |  |
Building and Improvements |  | 12,079 |  |  |  |  |
Total |  | 13,242 |  |  |  |  |
Accumulated Depreciation |  | $ 9,900 |  |  |  |  |
Depreciable Lives (Years) | [7] | (1) |  |  |  |  |
Reston Next | Development |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 0 |  |  |  |  |
Original Building |  | 0 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 514,182 |  |  |  |  |
Land and Improvements |  | 2,901 |  |  |  |  |
Building and Improvements |  | 250,135 |  |  |  |  |
Development and Construction in Progress |  | 261,146 |  |  |  |  |
Total |  | 514,182 |  |  |  |  |
Accumulated Depreciation |  | $ 1,631 |  |  |  |  |
Depreciable Lives (Years) |  | N/A |  |  |  |  |
Reston Next | Boston Properties Limited Partnership | Development |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 0 |  |  |  |  |
Original Building |  | 0 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 514,182 |  |  |  |  |
Land and Improvements |  | 2,901 |  |  |  |  |
Building and Improvements |  | 250,135 |  |  |  |  |
Development and Construction in Progress |  | 261,146 |  |  |  |  |
Total |  | 514,182 |  |  |  |  |
Accumulated Depreciation |  | $ 1,631 |  |  |  |  |
Depreciable Lives (Years) |  | N/A |  |  |  |  |
2100 Pennsylvania Avenue | Development |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 0 |  |  |  |  |
Original Building |  | 0 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 393,094 |  |  |  |  |
Land and Improvements |  | 185,203 |  |  |  |  |
Development and Construction in Progress |  | 207,891 |  |  |  |  |
Total |  | 393,094 |  |  |  |  |
Accumulated Depreciation |  | $ 5,941 |  |  |  |  |
Depreciable Lives (Years) |  | N/A |  |  |  |  |
2100 Pennsylvania Avenue | Boston Properties Limited Partnership | Development |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 0 |  |  |  |  |
Original Building |  | 0 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 393,094 |  |  |  |  |
Land and Improvements |  | 185,203 |  |  |  |  |
Building and Improvements |  | 0 |  |  |  |  |
Development and Construction in Progress |  | 207,891 |  |  |  |  |
Total |  | 393,094 |  |  |  |  |
Accumulated Depreciation |  | $ 5,941 |  |  |  |  |
Depreciable Lives (Years) |  | N/A |  |  |  |  |
325 Main Street | Development |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 174 |  |  |  |  |
Original Building |  | 0 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 286,000 |  |  |  |  |
Land and Improvements |  | 965 |  |  |  |  |
Development and Construction in Progress |  | 285,209 |  |  |  |  |
Total |  | 286,174 |  |  |  |  |
Accumulated Depreciation |  | $ 0 |  |  |  |  |
Depreciable Lives (Years) |  | N/A |  |  |  |  |
325 Main Street | Boston Properties Limited Partnership | Development |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 174 |  |  |  |  |
Original Building |  | 0 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 285,807 |  |  |  |  |
Land and Improvements |  | 772 |  |  |  |  |
Building and Improvements |  | 0 |  |  |  |  |
Development and Construction in Progress |  | 285,209 |  |  |  |  |
Total |  | 285,981 |  |  |  |  |
Accumulated Depreciation |  | $ 0 |  |  |  |  |
Depreciable Lives (Years) |  | N/A |  |  |  |  |
880 Winter Street [Member] | Development |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 15,597 |  |  |  |  |
Original Building |  | 37,255 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | (667) |  |  |  |  |
Land and Improvements |  | 15,597 |  |  |  |  |
Building and Improvements |  | 19,614 |  |  |  |  |
Development and Construction in Progress |  | 16,974 |  |  |  |  |
Total |  | 52,185 |  |  |  |  |
Accumulated Depreciation |  | $ 1,247 |  |  |  |  |
Depreciable Lives (Years) |  | N/A |  |  |  |  |
880 Winter Street [Member] | Boston Properties Limited Partnership | Development |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 15,597 |  |  |  |  |
Original Building |  | 37,255 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | (667) |  |  |  |  |
Land and Improvements |  | 15,597 |  |  |  |  |
Building and Improvements |  | 19,614 |  |  |  |  |
Development and Construction in Progress |  | 16,974 |  |  |  |  |
Total |  | 52,185 |  |  |  |  |
Accumulated Depreciation |  | $ 1,247 |  |  |  |  |
Depreciable Lives (Years) |  | N/A |  |  |  |  |
180 CityPoint | Land |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 0 |  |  |  |  |
Original Building |  | 0 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 50,776 |  |  |  |  |
Development and Construction in Progress |  | 50,776 |  |  |  |  |
Total |  | $ 50,776 |  |  |  |  |
Depreciable Lives (Years) |  | N/A |  |  |  |  |
180 CityPoint | Boston Properties Limited Partnership | Development |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 0 |  |  |  |  |
Original Building |  | 0 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 50,776 |  |  |  |  |
Development and Construction in Progress |  | 50,776 |  |  |  |  |
Total |  | 50,776 |  |  |  |  |
Accumulated Depreciation |  | $ 0 |  |  |  |  |
Depreciable Lives (Years) |  | N/A |  |  |  |  |
103 CityPoint | Land |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 0 |  |  |  |  |
Original Building |  | 0 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 14,663 |  |  |  |  |
Development and Construction in Progress |  | 14,663 |  |  |  |  |
Total |  | $ 14,663 |  |  |  |  |
Depreciable Lives (Years) |  | N/A |  |  |  |  |
103 CityPoint | Boston Properties Limited Partnership | Development |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 0 |  |  |  |  |
Original Building |  | 0 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 14,663 |  |  |  |  |
Development and Construction in Progress |  | 14,663 |  |  |  |  |
Total |  | 14,663 |  |  |  |  |
Accumulated Depreciation |  | $ 0 |  |  |  |  |
Depreciable Lives (Years) |  | N/A |  |  |  |  |
777 Harrison Street | Land |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 144,647 |  |  |  |  |
Original Building |  | 0 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 26,800 |  |  |  |  |
Building and Improvements |  | 47 |  |  |  |  |
Land held for development |  | 171,400 |  |  |  |  |
Total |  | 171,447 |  |  |  |  |
Accumulated Depreciation |  | $ 11 |  |  |  |  |
Depreciable Lives (Years) |  | N/A |  |  |  |  |
777 Harrison Street | Boston Properties Limited Partnership | Land |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 144,647 |  |  |  |  |
Original Building |  | 0 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 26,800 |  |  |  |  |
Building and Improvements |  | 47 |  |  |  |  |
Land held for development |  | 171,400 |  |  |  |  |
Total |  | 171,447 |  |  |  |  |
Accumulated Depreciation |  | $ 11 |  |  |  |  |
Depreciable Lives (Years) |  | N/A |  |  |  |  |
3625 - 3635 Peterson Way | Office Building [Member] |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 63,206 |  |  |  |  |
Original Building |  | 0 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 4,541 |  |  |  |  |
Land held for development |  | 67,747 |  |  |  |  |
Total |  | $ 67,747 |  |  |  |  |
Depreciable Lives (Years) | [6] | N/A |  |  |  |  |
3625 - 3635 Peterson Way | Boston Properties Limited Partnership | Land |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 63,206 |  |  |  |  |
Original Building |  | 0 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 4,541 |  |  |  |  |
Land held for development |  | 67,747 |  |  |  |  |
Total |  | 67,747 |  |  |  |  |
Accumulated Depreciation |  | $ 0 |  |  |  |  |
Depreciable Lives (Years) |  | N/A |  |  |  |  |
Back Bay Station Master Plan | Land |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 0 |  |  |  |  |
Original Building |  | 0 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 53,432 |  |  |  |  |
Land held for development |  | 53,432 |  |  |  |  |
Total |  | $ 53,432 |  |  |  |  |
Depreciable Lives (Years) |  | N/A |  |  |  |  |
Back Bay Station Master Plan | Boston Properties Limited Partnership | Land |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 0 |  |  |  |  |
Original Building |  | 0 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 53,432 |  |  |  |  |
Land held for development |  | 53,432 |  |  |  |  |
Total |  | 53,432 |  |  |  |  |
Accumulated Depreciation |  | $ 0 |  |  |  |  |
Depreciable Lives (Years) |  | N/A |  |  |  |  |
North First Master Plan | Land |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 35,004 |  |  |  |  |
Original Building |  | 0 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 3,941 |  |  |  |  |
Land held for development |  | 38,945 |  |  |  |  |
Total |  | $ 38,945 |  |  |  |  |
Depreciable Lives (Years) |  | N/A |  |  |  |  |
North First Master Plan | Boston Properties Limited Partnership | Land |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 35,004 |  |  |  |  |
Original Building |  | 0 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 3,941 |  |  |  |  |
Land held for development |  | 38,945 |  |  |  |  |
Total |  | 38,945 |  |  |  |  |
Accumulated Depreciation |  | $ 0 |  |  |  |  |
Depreciable Lives (Years) |  | N/A |  |  |  |  |
Plaza at Almaden | Land |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 0 |  |  |  |  |
Original Building |  | 0 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 37,418 |  |  |  |  |
Land held for development |  | 37,418 |  |  |  |  |
Total |  | $ 37,418 |  |  |  |  |
Depreciable Lives (Years) |  | N/A |  |  |  |  |
Plaza at Almaden | Boston Properties Limited Partnership | Land |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 0 |  |  |  |  |
Original Building |  | 0 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 37,418 |  |  |  |  |
Land held for development |  | 37,418 |  |  |  |  |
Total |  | 37,418 |  |  |  |  |
Accumulated Depreciation |  | $ 0 |  |  |  |  |
Depreciable Lives (Years) |  | N/A |  |  |  |  |
Reston Gateway Master Plan | Land |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 0 |  |  |  |  |
Original Building |  | 0 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 30,945 |  |  |  |  |
Land held for development |  | 30,945 |  |  |  |  |
Total |  | $ 30,945 |  |  |  |  |
Depreciable Lives (Years) |  | N/A |  |  |  |  |
Reston Gateway Master Plan | Boston Properties Limited Partnership | Land |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 0 |  |  |  |  |
Original Building |  | 0 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 30,945 |  |  |  |  |
Land held for development |  | 30,945 |  |  |  |  |
Total |  | 30,945 |  |  |  |  |
Accumulated Depreciation |  | $ 0 |  |  |  |  |
Depreciable Lives (Years) |  | N/A |  |  |  |  |
Springfield Metro Center | Land |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 0 |  |  |  |  |
Original Building |  | 0 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 19,887 |  |  |  |  |
Land held for development |  | 19,887 |  |  |  |  |
Total |  | $ 19,887 |  |  |  |  |
Depreciable Lives (Years) |  | N/A |  |  |  |  |
Springfield Metro Center | Boston Properties Limited Partnership | Land |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 0 |  |  |  |  |
Original Building |  | 0 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 19,887 |  |  |  |  |
Land held for development |  | 19,887 |  |  |  |  |
Total |  | 19,887 |  |  |  |  |
Accumulated Depreciation |  | $ 0 |  |  |  |  |
Depreciable Lives (Years) |  | N/A |  |  |  |  |
CityPoint South Master Plan | Land |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 0 |  |  |  |  |
Original Building |  | 0 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 14,890 |  |  |  |  |
Land held for development |  | 14,890 |  |  |  |  |
Total |  | $ 14,890 |  |  |  |  |
Depreciable Lives (Years) |  | N/A |  |  |  |  |
CityPoint South Master Plan | Boston Properties Limited Partnership | Land |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 0 |  |  |  |  |
Original Building |  | 0 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 14,890 |  |  |  |  |
Land held for development |  | 14,890 |  |  |  |  |
Total |  | 14,890 |  |  |  |  |
Accumulated Depreciation |  | $ 0 |  |  |  |  |
Depreciable Lives (Years) |  | N/A |  |  |  |  |
Kendall Center Master Plan | Land |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 0 |  |  |  |  |
Original Building |  | 0 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 8,381 |  |  |  |  |
Land held for development |  | 8,381 |  |  |  |  |
Total |  | $ 8,381 |  |  |  |  |
Depreciable Lives (Years) |  | N/A |  |  |  |  |
Kendall Center Master Plan | Boston Properties Limited Partnership | Land |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 0 |  |  |  |  |
Original Building |  | 0 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 8,381 |  |  |  |  |
Land held for development |  | 8,381 |  |  |  |  |
Total |  | 8,381 |  |  |  |  |
Accumulated Depreciation |  | $ 0 |  |  |  |  |
Depreciable Lives (Years) |  | N/A |  |  |  |  |
Broad Run Business Park | Land |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 0 |  |  |  |  |
Original Building |  | 0 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 2,405 |  |  |  |  |
Land held for development |  | 2,405 |  |  |  |  |
Total |  | $ 2,405 |  |  |  |  |
Depreciable Lives (Years) |  | N/A |  |  |  |  |
Broad Run Business Park | Boston Properties Limited Partnership | Land |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 0 |  |  |  |  |
Original Building |  | 0 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 2,405 |  |  |  |  |
Land held for development |  | 2,405 |  |  |  |  |
Total |  | 2,405 |  |  |  |  |
Accumulated Depreciation |  | $ 0 |  |  |  |  |
Depreciable Lives (Years) |  | N/A |  |  |  |  |
Weston Quarry | Land |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 0 |  |  |  |  |
Original Building |  | 0 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 1,249 |  |  |  |  |
Land held for development |  | 1,249 |  |  |  |  |
Total |  | $ 1,249 |  |  |  |  |
Depreciable Lives (Years) |  | N/A |  |  |  |  |
Weston Quarry | Boston Properties Limited Partnership | Land |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 0 |  |  |  |  |
Original Building |  | 0 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 1,249 |  |  |  |  |
Land held for development |  | 1,249 |  |  |  |  |
Total |  | 1,249 |  |  |  |  |
Accumulated Depreciation |  | $ 0 |  |  |  |  |
Depreciable Lives (Years) |  | N/A |  |  |  |  |
Reston Overlook Master Plan | Land |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 0 |  |  |  |  |
Original Building |  | 0 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 79 |  |  |  |  |
Land held for development |  | 79 |  |  |  |  |
Total |  | $ 79 |  |  |  |  |
Depreciable Lives (Years) |  | N/A |  |  |  |  |
Reston Overlook Master Plan | Boston Properties Limited Partnership | Land |  |  |  |  |  |  |
Original Cost |  |  |  |  |  |  |
Original Land |  | $ 0 |  |  |  |  |
Original Building |  | 0 |  |  |  |  |
Costs Capitalized Subsequent to Acquisition |  | 79 |  |  |  |  |
Land held for development |  | 79 |  |  |  |  |
Total |  | 79 |  |  |  |  |
Accumulated Depreciation |  | $ 0 |  |  |  |  |
Depreciable Lives (Years) |  | N/A |  |  |  |  |
[1] | Includes pre-development costs.
[2] | See Note 4.
[3] | Includes unamortized deferred financing costs totaling approximately $(32.1) million.
[4] | Includes Right of Use Assets - Finance Leases and Right of Use Assets - Operating Leases of approximately $214,165 and $169,778, respectively.
[5] | Includes Right of Use Assets - Finance Leases of approximately $23,342.
[6] | Depreciation of the buildings and improvements are calculated over lives ranging from the life of the lease to 40 years.
[7] | Depreciation of the buildings and improvements are calculated over lives ranging from the life of the lease to 40 years.

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