Quarterly report pursuant to Section 13 or 15(d)

Information by Business Segment (Details)

v2.4.0.8
Information by Business Segment (Details) (USD $)
In Thousands, unless otherwise specified
 3 Months Ended 9 Months Ended
Sep. 30, 2013
segment
Sep. 30, 2012
Sep. 30, 2013
segment
Sep. 30, 2012
Dec. 31, 2012
Segment Reporting [Abstract]          
Number of primary office property segments 10   10    
Segment financial information for real estate operations          
Revenues from real estate operations $ 124,561 $ 121,264 $ 371,913 $ 370,536  
Property operating expenses 44,885 43,699 133,605 134,293  
NOI from real estate operations 79,676 77,565 238,308 236,243  
Additions to long-lived assets 13,942 61,803      
Transfers from non-operating properties 42,842 28,146      
Segment assets 3,755,588 3,597,656 3,755,588 3,597,656 3,653,759
Operating Segment Total
          
Segment financial information for real estate operations          
Revenues from real estate operations     371,913 370,536  
Property operating expenses     133,605 134,293  
NOI from real estate operations     238,308 236,243  
Additions to long-lived assets     31,578 76,107  
Transfers from non-operating properties     197,600 129,348  
Segment assets 3,053,813 2,836,547 3,053,813 2,836,547  
Baltimore and Washington Corridor
          
Segment financial information for real estate operations          
Revenues from real estate operations 57,226 55,799 171,049 167,726  
Property operating expenses 18,780 18,534 57,030 56,677  
NOI from real estate operations 38,446 37,265 114,019 111,049  
Additions to long-lived assets 7,204 4,454 14,029 9,393  
Transfers from non-operating properties 8,706 12,431 37,270 42,488  
Segment assets 1,223,246 1,187,700 1,223,246 1,187,700  
Northern Virginia
          
Segment financial information for real estate operations          
Revenues from real estate operations 23,062 20,363 68,992 57,974  
Property operating expenses 7,999 7,115 24,020 21,270  
NOI from real estate operations 15,063 13,248 44,972 36,704  
Additions to long-lived assets 2,459 54,781 6,699 57,161  
Transfers from non-operating properties 26,355 12,979 37,209 12,979  
Segment assets 593,335 535,521 593,335 535,521  
San Antonio
          
Segment financial information for real estate operations          
Revenues from real estate operations 7,898 8,125 24,019 23,563  
Property operating expenses 4,061 4,272 12,427 11,998  
NOI from real estate operations 3,837 3,853 11,592 11,565  
Additions to long-lived assets 251 0 268 259  
Transfers from non-operating properties 0 0 0 464  
Segment assets 118,701 119,752 118,701 119,752  
Washington, DC - Capitol Riverfront
          
Segment financial information for real estate operations          
Revenues from real estate operations 4,295 4,389 12,716 12,515  
Property operating expenses 1,946 1,924 5,769 5,485  
NOI from real estate operations 2,349 2,465 6,947 7,030  
Additions to long-lived assets 86 414 484 116  
Transfers from non-operating properties 0 0 0 0  
Segment assets 99,852 106,090 99,852 106,090  
St. Mary's and King George Counties
          
Segment financial information for real estate operations          
Revenues from real estate operations 4,270 4,085 12,355 12,436  
Property operating expenses 1,299 1,241 3,715 3,524  
NOI from real estate operations 2,971 2,844 8,640 8,912  
Additions to long-lived assets 630 355 1,634 815  
Transfers from non-operating properties 0 24 12 218  
Segment assets 96,679 97,977 96,679 97,977  
Greater Baltimore
          
Segment financial information for real estate operations          
Revenues from real estate operations 10,703 11,918 32,246 41,954  
Property operating expenses 4,143 4,539 12,408 15,911  
NOI from real estate operations 6,560 7,379 19,838 26,043  
Additions to long-lived assets 1,707 1,055 1,761 5,390  
Transfers from non-operating properties 9 99 113 493  
Segment assets 305,947 283,996 305,947 283,996  
Suburban Maryland
          
Segment financial information for real estate operations          
Revenues from real estate operations 2,332 2,371 6,809 12,680  
Property operating expenses 862 1,041 2,393 5,357  
NOI from real estate operations 1,470 1,330 4,416 7,323  
Additions to long-lived assets 88 36 143 1,219  
Transfers from non-operating properties (183) (88) 337 793  
Segment assets 52,726 53,395 52,726 53,395  
Colorado Springs
          
Segment financial information for real estate operations          
Revenues from real estate operations 6,622 6,278 19,874 18,880  
Property operating expenses 2,371 2,432 7,014 6,754  
NOI from real estate operations 4,251 3,846 12,860 12,126  
Additions to long-lived assets 1,413 548 2,323 1,334  
Transfers from non-operating properties 1,860 315 4,540 2,611  
Segment assets 159,578 173,918 159,578 173,918  
Greater Philadelphia
          
Segment financial information for real estate operations          
Revenues from real estate operations 3,258 2,541 8,529 7,171  
Property operating expenses 924 663 2,482 1,851  
NOI from real estate operations 2,334 1,878 6,047 5,320  
Additions to long-lived assets 102 195 387 285  
Transfers from non-operating properties 3,414 1,843 28,031 11,233  
Segment assets 105,112 66,301 105,112 66,301  
Other
          
Segment financial information for real estate operations          
Revenues from real estate operations 3,819 3,589 10,878 10,977  
Property operating expenses 654 686 1,667 2,088  
NOI from real estate operations 3,165 2,903 9,211 8,889  
Additions to long-lived assets (84) (35) 3,588 124  
Transfers from non-operating properties (33) 548 20,925 394  
Segment assets 130,598 111,426 130,598 111,426  
Wholesale Data Center
          
Segment financial information for real estate operations          
Revenues from real estate operations 1,076 1,806 4,446 4,660  
Property operating expenses 1,846 1,252 4,680 3,378  
NOI from real estate operations (770) 554 (234) 1,282  
Additions to long-lived assets 86 0 262 11  
Transfers from non-operating properties 2,714 (5) 69,163 57,675  
Segment assets $ 168,039 $ 100,471 $ 168,039 $ 100,471