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Investments in Unconsolidated Joint Ventures (Statements of Operations of the Joint Ventures) (Details) - USD ($) $ in Thousands |  | 3 Months Ended | 6 Months Ended |
--- | --- | --- | --- | ---
Mar. 30, 2021 | Jun. 30, 2021 | Jun. 30, 2020 | Jun. 30, 2021 | Jun. 30, 2020 | Dec. 31, 2020 | [5]
Schedule of Equity Method Investments [Line Items] |  |  |  |  |  |  |  |  |
Total revenue |  |  | $ 713,807 |  | $ 654,773 | $ 1,427,502 |  | $ 1,407,329 |
Expenses |  |  |  |  |  |  |  |  |
Transaction costs |  |  | 751 |  | 332 | 1,082 |  | 947 |
Depreciation and amortization |  |  | 183,838 |  | 178,188 | 360,403 |  | 349,282 |
Total expenses |  |  | 476,348 |  | 460,507 | 961,148 |  | 941,694 |
Other income (expense) |  |  |  |  |  |  |  |  |
Interest expense |  |  | (106,319) |  | (107,142) | (214,221) |  | (208,733) |
Gains on sales of real estate |  |  | 7,756 |  | 203,767 | 7,756 |  | 613,932 |
Net income |  |  | 141,250 |  | 298,580 | 269,397 |  | 875,726 |
Income (Loss) from Equity Method Investments |  |  | (1,373) |  | 1,832 | 3,852 |  | 1,463 |
Write-off for accrued rent |  |  | 600 |  | 35,900 | 1,200 |  | 37,400 |
Unconsolidated Joint Ventures [Member] |  |  |  |  |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |  |  |  |  |
Total revenue | [1] |  | 91,226 |  | 89,563 | 178,492 |  | 182,766 |
Expenses |  |  |  |  |  |  |  |  |
Operating |  |  | 36,787 |  | 33,704 | 73,921 |  | 69,105 |
Transaction costs |  |  | 0 |  | 0 | 7 |  | 0 |
Depreciation and amortization |  |  | 33,627 |  | 37,390 | 67,730 |  | 69,425 |
Total expenses |  |  | 70,414 |  | 71,094 | 141,658 |  | 138,530 |
Other income (expense) |  |  |  |  |  |  |  |  |
Interest expense |  |  | (25,636) |  | (23,306) | (51,192) |  | (45,889) |
Gains on sales of real estate |  |  |  |  | 11,720 | 0 |  | 11,720 |
Net income |  |  | (4,824) |  | 6,883 | (14,358) |  | 10,067 |
Company's share of net income |  |  | (2,137) |  | 4,024 | (5,777) |  | 5,276 |
Gain on Sale of Investments |  |  | 0 | [2] | 0 | 10,257 | [2] | 0 |
Basis differential | [3] |  | 764 |  | (2,192) | (628) |  | (3,813) |
Income (Loss) from Equity Method Investments |  |  | (1,373) |  | 1,832 | 3,852 |  | 1,463 |
Straight-line rent adjustments |  |  | 5,000 |  | 8,500 | 6,100 |  | 18,200 |
Colorado Center [Member] |  |  |  |  |  |  |  |  |
Other income (expense) |  |  |  |  |  |  |  |  |
Straight-line rent adjustments |  |  | 100 |  | 400 | 600 |  | 900 |
Above and below market rent adjustments, net |  |  | $ 100 |  | $ 200 | $ 200 |  | $ 500 |
540 Madison Avenue [Member] |  |  |  |  |  |  |  |  |
Other income (expense) |  |  |  |  |  |  |  |  |
Ownership Percentage | [4] |  | 60.00% |  |  | 60.00% |  |  |
Annapolis Junction NFM, LLC [Member] |  |  |  |  |  |  |  |  |
Other income (expense) |  |  |  |  |  |  |  |  |
Gain on Sale of Investments |  | $ 10,300 |  |  |  | $ 10,300 |  |  |
Ownership Percentage |  | 50.00% |  |  |  |  |  |  | 50.00%
[1] | Includes straight-line rent adjustments of approximately $5.0 million and $8.5 million for the three months ended June 30, 2021 and 2020, respectively, and approximately $6.1 million and $18.2 million for the six months ended June 30, 2021 and 2020, respectively.
[2] | During the six months ended June 30, 2021, the Company completed the sale of its 50% ownership interest in Annapolis Junction NFM LLC. The Company recognized a gain on sale of investment of approximately $10.3 million.
[3] | Includes straight-line rent adjustments of approximately $0.1 million and $0.4 million for the three months ended June 30, 2021 and 2020, respectively, and approximately $0.6 million and $0.9 million for the six months ended June 30, 2021 and 2020, respectively. Also includes net above-/below-market rent adjustments of approximately $0.1 million and $0.2 million for the three months ended June 30, 2021 and 2020, respectively, and approximately $0.2 million and $0.5 million for the six months ended June 30, 2021 and 2020, respectively.
[4] | T he property was sold on June 27, 2019. As of December 31, 2020, the investment consisted of undistributed cash. All remaining cash has been distributed as of June 30, 2021.
[5] | On March 30, 2021, the Company sold its interest in the joint venture to the partner. See below for additional details.

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