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Real Estate Activity During the Six Months Ended June 30, 2013 (Summary Of The Discontinued Operations Related To Montvale Center, 303 Almaden Blvd and Bedford Business Park) (Details) (USD $) In Thousands, unless otherwise specified | 3 Months Ended | 6 Months Ended | 3 Months Ended | 6 Months Ended | 3 Months Ended
--- | --- | --- | --- | --- | ---
Jun. 30, 2013 | Jun. 30, 2012 | Jun. 30, 2013 | Jun. 30, 2012 | Jun. 30, 2013 Montvale Center and 303 Almaden Blvd [Member] [Member] | Jun. 30, 2012 Montvale Center, 303 Almaden Blvd and Bedford Business Park [Member] | Jun. 30, 2012 Montvale Center, 303 Almaden Blvd and Bedford Business Park [Member] | Jun. 30, 2013 303 Almaden Blvd [Member] | Mar. 31, 2013 303 Almaden Blvd [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |  |  |  |  |  |  |  |  |
Total revenue | $ 515,320 | $ 471,349 | $ 998,334 | $ 915,042 | $ 3,376 | $ 3,263 | $ 7,784 | $ 1,529 |
Expenses |  |  |  |  |  |  |  |  |
Operating |  |  |  |  | 1,486 | 1,489 | 3,392 | 656 |
Depreciation and amortization | 134,604 | 111,168 | 255,199 | 219,630 | 596 | 907 | 2,310 | 0 |
Total expenses | 344,505 | 298,030 | 697,084 | 598,156 | 2,082 | 2,396 | 5,702 | 656 |
Operating income | 170,815 | 173,319 | 301,250 | 316,886 | 1,294 | 867 | 2,082 | 873 |
Other expense |  |  |  |  |  |  |  |  |
Interest expense | (103,140) | (99,901) | (203,573) | (203,138) | (360) | (649) | (1,294) | 0 |
Income from discontinued operations | 873 | 218 | 934 | 788 | 934 | 218 | 788 | 873 |
Noncontrolling interest in income (loss) from discontinued operations - common units of the Operating Partnership | (88) | (4,075) | (1,900) | (4,159) | (94) | (23) | (84) | (88) |
Income (loss) from discontinued operations attributable to Boston Properties, Inc. | 785 | 33,020 | 15,975 | 33,506 | 840 | 195 | 704 | 785 |
Gain on sale of real estate from discontinued operations | 0 | 36,877 | 0 | 36,877 | 0 | 36,877 | 36,877 | 0 |
Gain on forgiveness of debt from discontinued operations | 0 | 0 | 20,182 | 0 | 20,182 | 0 | 0 | 0 |
Impairment loss from discontinued operations | 0 | 0 | 3,241 | 0 | 3,241 | 0 | 0 | 0 | 3,200
Noncontrolling interest in gain on the sale of real estate, gain on forgiveness of debt from discontinued operations - common units of the Operating Partnership |  |  |  |  | 1,806 | 4,052 | 4,075 | 0 |
Gain on Sale of Real Estate, Gain On Forgiveness of Debt and Impairment Losses from Discontinued Operations Attributable to Company |  |  |  |  | $ 15,135 | $ 32,825 | $ 32,802 | $ 0 |

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