Organization and Basis of Presentation (Details)	Sep. 30, 2013 building
Real Estate Properties [Line Items]
Number of buildings	14
Office Properties [Member]
Real Estate Properties [Line Items]
Number of buildings	103	[1]
Rentable square feet	12,536,495	[1]
Number of Tenants	654	[1]
Percentage Occupied	92.20%	[1]
Other Segments [Member] | Properties Held for Sale [Member]
Real Estate Properties [Line Items]
Number of buildings	14	[2]
Rentable square feet	1,159,185	[2]
Other Segments [Member] | Development Properties [Member]
Real Estate Properties [Line Items]
Number of buildings	5	[3]
Rentable square feet	1,516,000	[3]
Other Segments [Member] | Lease Up Properties [Member]
Real Estate Properties [Line Items]
Number of buildings	2
Rentable square feet	508,000
San Diego, California [Member] | Other Segments [Member] | Properties Held for Sale [Member]
Real Estate Properties [Line Items]
Number of buildings	13	[3],[4]
Anaheim, California [Member] | Other Segments [Member] | Properties Held for Sale [Member]
Real Estate Properties [Line Items]
Number of buildings	1	[3],[5]

[1] Excludes 13 properties located in San Diego, California and one property in Anaheim, California that were held for sale at September 30, 2013 (see Note 12 “Discontinued Operations”).

[2] Includes 13 properties located in San Diego, California and one property in Anaheim, California (see Note 12).

[3] Estimated rentable square feet upon completion.

[4] The San Diego Properties included the following: 4910 Directors Place, 10020 Pacific Mesa Boulevard, 6055 Lusk Avenue, 5010 and 5005 Wateridge Vista Drive, 15435 and 15445 Innovation Drive, and 15051, 15073, 15231, 15253, 15333 and 15378 Avenue of Science.

[5] We closed on the disposition of this property on October 2, 2013. The sales price was $9.6 million.