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Real Estate Activity During the Nine Months Ended September 30, 2014 (Summary Of The Discontinued Operations Related To Montvale Center, 303 Almaden Blvd, 1301 New York Avenue, One Preserve Parkway and 10 & 20 Burlington Mall Road) (Details) (USD $) In Thousands, unless otherwise specified | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2014 | Sep. 30, 2013 | Sep. 30, 2014 | Sep. 30, 2013
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |  |  |  |
Total revenue | $ 618,803 | $ 571,481 | $ 1,783,291 | $ 1,559,340
Expenses |  |  |  |
Depreciation and amortization | 157,245 | 153,253 | 466,143 | 406,162
Total expenses | 404,000 | 384,728 | 1,190,318 | 1,076,212
Operating income | 214,803 | 186,753 | 592,973 | 483,128
Other expense |  |  |  |
Interest expense | 113,308 | 122,173 | 337,839 | 325,746
Income from discontinued operations | 0 | 1,677 | 0 | 7,486
Noncontrolling interest in income (loss) from discontinued operations - common units of the Operating Partnership | 0 | (8,970) | 0 | (11,450)
Income from discontinued operations attributable to Boston Properties, Inc. |  | 79,155 |  | 99,425
Gain on sale of real estate from discontinued operations | 0 | 86,448 | 0 | 86,448
Gain on forgiveness of debt from discontinued operations | 0 | 0 | 0 | 20,182
Impairment loss from discontinued operations | 0 | 0 | 0 | (3,241)
Montvale Center, 303 Almaden Blvd, 1301 New York Avenue, One Preserve Parkway and 10 & 20 Burlington Mall Road [Member] |  |  |  |
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |  |  |  |
Total revenue |  |  |  | 17,962
Expenses |  |  |  |
Operating |  |  |  | 6,290
Depreciation and amortization |  |  |  | 3,826
Total expenses |  |  |  | 10,116
Operating income |  |  |  | 7,846
Other expense |  |  |  |
Interest expense |  |  |  | 360
Income from discontinued operations |  |  |  | 7,486
Noncontrolling interest in income (loss) from discontinued operations - common units of the Operating Partnership |  |  |  | (752)
Income from discontinued operations attributable to Boston Properties, Inc. |  |  |  | 6,734
Gain on sale of real estate from discontinued operations |  |  |  | 86,448
Gain on forgiveness of debt from discontinued operations |  |  |  | 20,182
Impairment loss from discontinued operations |  |  |  | (3,241)
Noncontrolling interest in gain on forgiveness of debt from discontinued operations - common units of the Operating Partnership |  |  |  | (10,698)
Gain on forgiveness of debt and impairment losses from discontinued operations attributable to Boston Properties, Inc. |  |  |  | 92,691
1301 New York Avenue, One Preserve Parkway and 10 & 20 Burlington Mall Road [Member] |  |  |  |
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |  |  |  |
Total revenue |  | 4,112 |  |
Expenses |  |  |  |
Operating |  | 1,495 |  |
Depreciation and amortization |  | 940 |  |
Total expenses |  | 2,435 |  |
Operating income |  | 1,677 |  |
Other expense |  |  |  |
Interest expense |  | 0 |  |
Income from discontinued operations |  | 1,677 |  |
Noncontrolling interest in income (loss) from discontinued operations - common units of the Operating Partnership |  | (167) |  |
Income from discontinued operations attributable to Boston Properties, Inc. |  | 1,510 |  |
Gain on sale of real estate from discontinued operations |  | 86,448 |  |
Gain on forgiveness of debt from discontinued operations |  | 0 |  |
Impairment loss from discontinued operations |  | 0 |  |
Noncontrolling interest in gain on forgiveness of debt from discontinued operations - common units of the Operating Partnership |  | (8,803) |  |
Gain on forgiveness of debt and impairment losses from discontinued operations attributable to Boston Properties, Inc. |  | $ 77,645 |  |

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