Organization and Basis of Presentation (Details Textuals) (USD $) In Millions, unless otherwise specified	3 Months Ended	6 Months Ended
Jun. 30, 2011	Jun. 30, 2011	Dec. 31, 2010	Jun. 30, 2010
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Number of Buildings	8	8
Organization and Basis of Presentation Details (Textuals) [Abstract]
Cost of Buildings	$ 413.0	$ 413.0
Number of properties of the company in Washington	6	6
Stabilized Occupancy		95.00%
Lease-up properties	0	0
Years single tenant occupied property under redevelopment		25 years
Office space under redevelopment		300,000
Office space under committed redevelopment	98,000	98,000
Percentage of general partnership interest owned by the company in the Operating Partnership	97.10%	97.10%	96.80%	96.70%
Percentage of Common limited partnership interest owned by certain non-affiliated investors and certain directors and officers of the Company in the Operating Partnership	2.90%	2.90%	3.20%	3.30%
Percentage of General partnership interest owned by wholly-owned subsidiary of the Company	1.00%	1.00%
Percentage of limited partnership interest owned by Operating Partnership	99.00%	99.00%
Threshhold limits for segment reporting	10.00%	10.00%
2355, 2365, 2375 Northside Drive San Diego, CA [Member]
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Number of Buildings	3	3
Office Properties [Member]
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Number of Buildings	8	8

Properties recently developed or redeveloped that have not yet reached 95% occupancy and are within one year following cessation of major construction activities.

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- Definition

Number of properties of the company located in Washington.

+ Details

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- Definition

Office space under committed redevelopment.

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- Definition

Office space under redevelopment.

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- Definition

Organization And Basis Of Presentation.

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- Definition

Percentage of General partnership interest owned by wholly-owned subsidiary of the Company.

+ Details

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- Definition

Percentage of limited partnership interest owned by Operating Partnership.

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- Definition

Stabilized occupancy.

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- Definition

Threshhold limits for segment reporting.

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- Definition

Years single tenant occupied property under redevelopment was over 25 years.

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- Definition

The total cost of the acquired entity including the cash paid to shareholders of acquired entities, fair value of debt and equity securities issued to shareholders of acquired entities, the fair value of the liabilities assumed, and direct costs of the acquisition.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 141
-Paragraph 51
-Subparagraph d
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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The equity interest of noncontrolling shareholders, partners or other equity holders in consolidated entity.

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The parent entity's interest in net assets of the subsidiary, expressed as a percentage.

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- Definition

The number of real estate properties owned as of the balance sheet date.

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