Organization And Basis Of Presentation (Details)
| 9 Months Ended |
|---|
Sep. 30, 2011
sqft
years |
|---|
| Number of properties owned or investment interests | 278 |
| Aggregate square feet of the property owned or investment interest | 32,400,000 |
| Number of locations of properties | 5 |
Office And Office/Flex Buildings [Member] | |
| Number of properties owned or investment interests | 266 |
| Aggregate square feet of the property owned or investment interest | 32,000,000 |
Office Buildings [Member] | |
| Number of properties owned or investment interests | 8 |
| Aggregate square feet of the property owned or investment interest | 1,200,000 |
Industrial/Warehouse Facilities [Member] | |
| Number of properties owned or investment interests | 6 |
| Aggregate square feet of the property owned or investment interest | 387,400 |
Retail [Member] | |
| Number of properties owned or investment interests | 2 |
| Aggregate square feet of the property owned or investment interest | 17,300 |
Hotels [Member] | |
| Number of properties owned or investment interests | 1 |
Land Leased [Member] | |
| Number of properties owned or investment interests | 3 |