Investment in Real Estate (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Investment in Real Estate
Land	$ 94,593	$ 94,593
Buildings and Improvements	2,015,530	1,989,731
Construction in Progress	437,794	394,474
Total investments in real estate	2,547,917	2,478,798
Boston
Investment in Real Estate
Land	5,154	5,154
Buildings and Improvements	119,803	119,227
Construction in Progress	3,005	931
Total investments in real estate	127,962	125,312
Chicago
Investment in Real Estate
Land	5,493	5,493
Buildings and Improvements	115,909	115,699
Construction in Progress	110,768	100,118
Total investments in real estate	232,170	221,310
Denver
Investment in Real Estate
Buildings and Improvements	34,938	32,659
Construction in Progress	386	2,461
Total investments in real estate	35,324	35,120
Los Angeles
Investment in Real Estate
Land	18,672	18,672
Buildings and Improvements	377,134	376,525
Construction in Progress	81,178	60,178
Total investments in real estate	476,984	455,375
Miami
Investment in Real Estate
Land	728	728
Buildings and Improvements	14,641	14,491
Construction in Progress		133
Total investments in real estate	15,369	15,352
New York
Investment in Real Estate
Land	2,729	2,729
Buildings and Improvements	173,080	155,746
Construction in Progress	54,719	56,271
Total investments in real estate	230,528	214,746
Northern Virginia
Investment in Real Estate
Land	21,856	21,856
Buildings and Improvements	401,645	398,742
Construction in Progress	101,718	101,619
Total investments in real estate	525,219	522,217
San Francisco Bay
Investment in Real Estate
Land	39,961	39,961
Buildings and Improvements	778,380	776,642
Construction in Progress	86,020	72,763
Total investments in real estate	$ 904,361	$ 889,366

The current amount of expenditures for a real estate project that has not yet been completed.

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Aggregate of the carrying amounts as of the balance sheet date of investments in building and building improvements.

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Amount before accumulated depletion of real estate held for productive use, excluding land held for sale.

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Amount of real estate investment property which may include the following: (1) land available-for-sale; (2) land available-for-development; (3) investments in building and building improvements; (4) tenant allowances; (5) developments in-process; (6) rental properties; and (7) other real estate investments.

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