v2.4.0.8

Segment Information (Schedule Of Segment Reporting By Geographic Area And Property Type) (Details) (USD $) In Thousands, unless otherwise specified | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2013 | Jun. 30, 2012 | Jun. 30, 2013 | Jun. 30, 2012
Segment Reporting Information [Line Items] |  |  |  |
Rental Revenue: Class A Office | $ 475,965 | $ 436,758 | $ 926,527 | $ 851,266
Rental Revenue: Office/Technical | 14,896 | 9,942 | 24,743 | 19,685
Rental Revenue: Residential | 5,484 | 5,036 | 11,062 | 9,517
Rental Revenue: Hotel | 11,118 | 10,049 | 19,409 | 16,865
Total revenue | 507,463 | 461,785 | 981,741 | 897,333
Rental Revenue: % of Grand Totals | 100.00% | 100.00% | 100.00% | 100.00%
Rental Expenses: Class A Office | 173,237 | 155,944 | 340,298 | 306,500
Rental Expenses: Office/Technical | 3,770 | 2,654 | 6,596 | 5,225
Rental Expenses: Residential | 2,830 | 2,574 | 5,563 | 5,289
Rental Expenses: Hotel | 7,335 | 6,616 | 14,379 | 12,715
Rental Expenses: Total | 187,172 | 167,788 | 366,836 | 329,729
Rental Expenses: % Of Grand Totals | 100.00% | 100.00% | 100.00% | 100.00%
Net operating Income | 320,291 | 293,997 | 614,905 | 567,604
Net operating Income: % of Grand Totals | 100.00% | 100.00% | 100.00% | 100.00%
Boston [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Rental Revenue: Class A Office | 164,855 | 157,642 | 326,358 | 298,650
Rental Revenue: Office/Technical | 5,538 | 5,744 | 11,191 | 11,343
Rental Revenue: Residential | 1,065 | 1,013 | 2,132 | 1,896
Rental Revenue: Hotel | 11,118 | 10,049 | 19,409 | 16,865
Total revenue | 182,576 | 174,448 | 359,090 | 328,754
Rental Revenue: % of Grand Totals | 35.98% | 37.78% | 36.58% | 36.64%
Rental Expenses: Class A Office | 63,181 | 60,504 | 128,913 | 118,337
Rental Expenses: Office/Technical | 1,627 | 1,652 | 3,414 | 3,152
Rental Expenses: Residential | 407 | 367 | 850 | 757
Rental Expenses: Hotel | 7,335 | 6,616 | 14,379 | 12,715
Rental Expenses: Total | 72,550 | 69,139 | 147,556 | 134,961
Rental Expenses: % Of Grand Totals | 38.76% | 41.21% | 40.22% | 40.93%
Net operating Income | 110,026 | 105,309 | 211,534 | 193,793
Net operating Income: % of Grand Totals | 34.35% | 35.82% | 34.40% | 34.14%
New York [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Rental Revenue: Class A Office | 143,305 | 122,657 | 265,401 | 240,246
Rental Revenue: Office/Technical | 0 | 0 | 0 | 0
Rental Revenue: Residential | 0 | 0 | 0 | 0
Rental Revenue: Hotel | 0 | 0 | 0 | 0
Total revenue | 143,305 | 122,657 | 265,401 | 240,246
Rental Revenue: % of Grand Totals | 28.24% | 26.56% | 27.03% | 26.77%
Rental Expenses: Class A Office | 48,205 | 38,936 | 90,092 | 77,443
Rental Expenses: Office/Technical | 0 | 0 | 0 | 0
Rental Expenses: Residential | 0 | 0 | 0 | 0
Rental Expenses: Hotel | 0 | 0 | 0 | 0
Rental Expenses: Total | 48,205 | 38,936 | 90,092 | 77,443
Rental Expenses: % Of Grand Totals | 25.75% | 23.21% | 24.56% | 23.49%
Net operating Income | 95,100 | 83,721 | 175,309 | 162,803
Net operating Income: % of Grand Totals | 29.69% | 28.48% | 28.51% | 28.68%
Princeton [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Rental Revenue: Class A Office | 14,853 | 15,617 | 31,280 | 30,467
Rental Revenue: Office/Technical | 0 | 0 | 0 | 0
Rental Revenue: Residential | 0 | 0 | 0 | 0
Rental Revenue: Hotel | 0 | 0 | 0 | 0
Total revenue | 14,853 | 15,617 | 31,280 | 30,467
Rental Revenue: % of Grand Totals | 2.93% | 3.38% | 3.19% | 3.40%
Rental Expenses: Class A Office | 7,667 | 7,691 | 15,314 | 15,049
Rental Expenses: Office/Technical | 0 | 0 | 0 | 0
Rental Expenses: Residential | 0 | 0 | 0 | 0
Rental Expenses: Hotel | 0 | 0 | 0 | 0
Rental Expenses: Total | 7,667 | 7,691 | 15,314 | 15,049
Rental Expenses: % Of Grand Totals | 4.10% | 4.58% | 4.17% | 4.56%
Net operating Income | 7,186 | 7,926 | 15,966 | 15,418
Net operating Income: % of Grand Totals | 2.24% | 2.70% | 2.60% | 2.72%
San Francisco [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Rental Revenue: Class A Office | 53,331 | 52,102 | 106,002 | 102,766
Rental Revenue: Office/Technical | 5,327 | 144 | 5,478 | 196
Rental Revenue: Residential | 0 | 0 | 0 | 0
Rental Revenue: Hotel | 0 | 0 | 0 | 0
Total revenue | 58,658 | 52,246 | 111,480 | 102,962
Rental Revenue: % of Grand Totals | 11.56% | 11.31% | 11.35% | 11.47%
Rental Expenses: Class A Office | 21,264 | 20,507 | 41,136 | 39,924
Rental Expenses: Office/Technical | 1,116 | 38 | 1,151 | 62
Rental Expenses: Residential | 0 | 0 | 0 | 0
Rental Expenses: Hotel | 0 | 0 | 0 | 0
Rental Expenses: Total | 22,380 | 20,545 | 42,287 | 39,986
Rental Expenses: % Of Grand Totals | 11.96% | 12.24% | 11.53% | 12.13%
Net operating Income | 36,278 | 31,701 | 69,193 | 62,976
Net operating Income: % of Grand Totals | 11.33% | 10.78% | 11.25% | 11.10%
Washington, DC [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Rental Revenue: Class A Office | 99,621 | 88,740 | 197,486 | 179,137
Rental Revenue: Office/Technical | 4,031 | 4,054 | 8,074 | 8,146
Rental Revenue: Residential | 4,419 | 4,023 | 8,930 | 7,621
Rental Revenue: Hotel | 0 | 0 | 0 | 0
Total revenue | 108,071 | 96,817 | 214,490 | 194,904
Rental Revenue: % of Grand Totals | 21.29% | 20.97% | 21.85% | 21.72%
Rental Expenses: Class A Office | 32,920 | 28,306 | 64,843 | 55,747
Rental Expenses: Office/Technical | 1,027 | 964 | 2,031 | 2,011
Rental Expenses: Residential | 2,423 | 2,207 | 4,713 | 4,532
Rental Expenses: Hotel | 0 | 0 | 0 | 0
Rental Expenses: Total | 36,370 | 31,477 | 71,587 | 62,290
Rental Expenses: % Of Grand Totals | 19.43% | 18.76% | 19.52% | 18.89%
Net operating Income | $ 71,701 | $ 65,340 | $ 142,903 | $ 132,614
Net operating Income: % of Grand Totals | 22.39% | 22.22% | 23.24% | 23.36%

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