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Investments in Unconsolidated Joint Ventures (Statements of Operations of the Joint Ventures) (Details) - USD ($) $ in Thousands | 3 Months Ended
--- | ---
Mar. 31, 2019 | Mar. 31, 2018
Schedule of Equity Method Investments [Line Items] |  |  |
Total revenue |  | $ 725,767 | $ 661,151
Expenses |  |  |
Depreciation and amortization |  | 164,594 | 165,797
Total expenses |  | 475,591 | 452,999
Other expense |  |  |
Interest expense |  | 101,009 | 90,220
Net income |  | 131,159 | 216,312
Income from unconsolidated joint ventures |  | 213 | 461
Unconsolidated Joint Ventures [Member] |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |
Total revenue | [1] | 82,955 | 56,486
Expenses |  |  |
Operating |  | 30,499 | 22,849
Depreciation and amortization |  | 28,646 | 14,725
Total expenses |  | 59,145 | 37,574
Other expense |  |  |
Interest expense |  | 20,757 | 14,424
Net income |  | 3,053 | 4,488
Company's share of net income (loss) |  | 1,584 | 1,826
Basis differential | [2] | (1,371) | (1,365)
Income from unconsolidated joint ventures |  | 213 | 461
Straight-line rent adjustments |  | 5,800 | 1,800
Colorado Center [Member] | Unconsolidated Joint Ventures [Member] |  |  |
Other expense |  |  |
Straight-line rent adjustments |  | 500 | 700
"Above" and "below" market rent adjustments, net |  | $ 400 | $ 400
[1] | Includes straight-line rent adjustments of approximately $5.8 million and $1.8 million for the three months ended March 31, 2019 and 2018, respectively
[2] | Includes straight-line rent adjustments of approximately $0.5 million and $0.7 million for the three months ended March 31, 2019 and 2018, respectively. Also includes net above-/below-market rent adjustments of approximately $0.4 million and $0.4 million for the three months ended March 31, 2019 and 2018, respectively

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