Consolidated Statements of Cash Flows Parenthetical (USD $)	9 Months Ended
Sep. 30, 2011 Office portfolio 200,000 square feet, located in Oakland, California [Member]	Sep. 30, 2010 Consolidation of controlling interest in Fairways 340, Llc previously accounted for under the Equity Method [Member]	Sep. 30, 2011 Controlling interest in land located in Kent, Washington [Member]
Supplemental disclosure of non-cash investing activities:
Increase in real estate	$ 17,680,000	$ 71,862,000
Increase in accounts payable due to acquisition	87,000
Increase in accrued expenses and other liabilites	991,000	323,000
Increase in mortgage loans payable	16,000,000	66,501,000
Square footage of acquired office portfolio	200,000
Decrease in real estate due to the sale of controlling interest in land			696,000
Increase in accounts receivable due to consolidation of subsidiaries	(44,000)	171,000
Increase (Decrease) in Prepaid Expense and Other Assets	50,000
Decrease in investment in joint venture due to consolidation of subsidiaries		6,256,000
Increase in other assets due to consolidation of subsidiaries		$ 3,174,000

Increase (decrease) in investment in joint venture

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- Definition

The increase (decrease) during the reporting period in the aggregate amount of liabilities incurred (and for which invoices have typically been received) and payable to vendors for goods and services received that are used in an entity's business.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 95

-Paragraph 28

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (a)

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- Definition

The increase (decrease) during the reporting period in amount due within one year (or one business cycle) from customers for the credit sale of goods and services.

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- Definition

The increase (decrease) during the reporting period in the aggregate amount of expenses incurred but not yet paid.

+ References

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The increase (decrease) during the reporting period in other assets used in operating activities not separately disclosed in the statement of cash flows. May include changes in other current assets, other noncurrent assets, or a combination of other current and noncurrent assets.

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The increase (decrease) during the reporting period in the value of prepaid expenses and other assets not separately disclosed in the statement of cash flows, for example, deferred expenses, intangible assets,or income taxes.

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- Definition

The cash outflow from the acquisition of a piece of land, anything permanently fixed to it, including buildings, structures on it and so forth; includes real estate intended to generate income for the owner; excludes real estate acquired for use by the owner.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 95

-Paragraph 17

-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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-Publisher FASB

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-Topic 230

-SubTopic 10

-Section 45

-Paragraph 13

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- Definition

The cash inflow from amounts received from issuance of long-term debt that is wholly or partially secured by collateral. Excludes proceeds from tax exempt secured debt.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

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-Subparagraph (b)

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-Glossary Financing Activities

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- Definition

Cash received from the sale of real estate that is held for investment, that is, it is part of an investing activity during the period.

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

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- Definition

The amount of square footage related to a real estate property.

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