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v3.20.1

Real Estate (Narrative) (Details) $ in Thousands |  |  | 1 Months Ended | 2 Months Ended | 3 Months Ended |
--- | --- | --- | --- | --- | --- | ---
Feb. 20, 2020 USD ($) ft² Buildings | Jan. 28, 2020 USD ($) ft² Buildings | Jan. 27, 2020 USD ($) | Feb. 19, 2020 USD ($) | Mar. 31, 2020 USD ($) | Mar. 31, 2019 USD ($) | Mar. 26, 2020 ft²
Real Estate Properties [Line Items] |  |  |  |  |  |  |  |
Proceeds from sales of real estate |  |  |  |  | $ 259,489 |  | $ 20,019 |
Gains (loss) on sales of real estate |  |  |  |  | 410,165 |  | (905) |
Payments to Acquire Equity Method Investments |  |  |  |  | 89,997 |  | 26,995 |
Revenues |  |  |  |  | 752,556 |  | 725,767 |
New Dominion Technology Park [Member] |  |  |  |  |  |  |  |
Real Estate Properties [Line Items] |  |  |  |  |  |  |  |
Net Rentable Area (in sf) | ft² | 493,000 |  |  |  |  |  |  |
Contractual Sales Price | $ 256,000 |  |  |  |  |  |  |
Proceeds from sales of real estate | 254,000 |  |  |  |  |  |  |
Gains (loss) on sales of real estate | $ 192,300 |  |  |  |  |  |  |
Operating Income (Loss) |  |  |  | $ 1,600 |  |  | 2,100 |
number of buildings | Buildings | 2 |  |  |  |  |  |  |
Gateway Center [Member] |  |  |  |  |  |  |  |
Real Estate Properties [Line Items] |  |  |  |  |  |  |  |
Gains (loss) on sales of real estate |  | $ 217,700 |  |  |  |  |  |
Operating Income (Loss) |  |  | $ 200 |  |  |  | 2,900 |
425 Fourth Street [Member] |  |  |  |  |  |  |  |
Real Estate Properties [Line Items] |  |  |  |  |  |  |  |
Aggregate purchase price |  | $ 134,100 |  |  |  |  |  |
Net Rentable Area (in sf) | ft² |  | 804,000 |  |  |  |  |  |
17Fifty Presidents Street [Member] |  |  |  |  |  |  |  |
Real Estate Properties [Line Items] |  |  |  |  |  |  |  |
Net Rentable Area (in sf) | ft² |  |  |  |  |  |  |  | 276,000
Leased percentage |  |  |  |  |  |  |  | 100.00%
Boston Properties Limited Partnership |  |  |  |  |  |  |  |
Real Estate Properties [Line Items] |  |  |  |  |  |  |  |
Proceeds from sales of real estate |  |  |  |  | 259,489 |  | 20,019 |
Gains (loss) on sales of real estate |  |  |  |  | 419,654 |  | (905) |
Payments to Acquire Equity Method Investments |  |  |  |  | 89,997 |  | 26,995 |
Revenues |  |  |  |  | $ 752,556 |  | $ 725,767 |
Gateway Commons Complex [Member] |  |  |  |  |  |  |  |
Real Estate Properties [Line Items] |  |  |  |  |  |  |  |
Net Rentable Area (in sf) | ft² |  | 768,000 |  |  |  |  |  |
Payments to Acquire Equity Method Investments |  | $ 350,000 |  |  |  |  |  |
Ownership Percentage |  | 50.00% |  |  | 50.00% | [1] |  |
number of buildings | Buildings |  | 3 |  |  |  |  |  |
Gateway Commons Complex prior to deferred contribution [Member] [Member] |  |  |  |  |  |  |  |
Real Estate Properties [Line Items] |  |  |  |  |  |  |  |
Ownership Percentage |  | 55.00% |  |  |  |  |  |
Gateway Commons Complex Future Development[Member] [Member] |  |  |  |  |  |  |  |
Real Estate Properties [Line Items] |  |  |  |  |  |  |  |
Ownership Percentage |  | 49.00% |  |  |  |  |  |
Joint Venture Partner [Member] | Gateway Commons Complex [Member] |  |  |  |  |  |  |  |
Real Estate Properties [Line Items] |  |  |  |  |  |  |  |
Net Rentable Area (in sf) | ft² |  | 768,000 |  |  |  |  |  |
Payments to Acquire Equity Method Investments |  | $ 280,800 |  |  |  |  |  |
Future payment to acquire interest in equity method investment |  | $ 69,200 |  |  |  |  |  |
Ownership Percentage |  | 50.00% |  |  |  |  |  |
number of buildings | Buildings |  | 3 |  |  |  |  |  |
Joint Venture Partner [Member] | Gateway Commons Complex Future Development[Member] [Member] |  |  |  |  |  |  |  |
Real Estate Properties [Line Items] |  |  |  |  |  |  |  |
Ownership Percentage |  | 51.00% |  |  |  |  |  |
Boston Properties Limited Partnership | New Dominion Technology Park [Member] |  |  |  |  |  |  |  |
Real Estate Properties [Line Items] |  |  |  |  |  |  |  |
Gains (loss) on sales of real estate | $ 197,100 |  |  |  |  |  |  |
Boston Properties Limited Partnership | Gateway Center [Member] |  |  |  |  |  |  |  |
Real Estate Properties [Line Items] |  |  |  |  |  |  |  |
Gains (loss) on sales of real estate |  | $ 222,400 |  |  |  |  |  |
[1] | As a result of the partner’s deferred contribution, the Company has an initial approximately 55% interest in the joint venture. Future development projects will be owned 49% by the Company and 51% by its partner.

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