Area of Property in Square foot

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- Definition

Distributions received from the venture during the current period.

+ Details

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Balance Type:	debit
Period Type:	duration

- Definition

Management Leasing And Other Services Fees.

+ Details

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Balance Type:	credit
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- Definition

Payment made pursuant to the participation rights.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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- Definition

Company share of gain or loss recognized by the venture on sale of property.

+ Details

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- Definition

Venture Gain Loss On Sale Of Real Estate

+ Details

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Balance Type:	credit
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- Definition

Revenue recognized by the venture from the sale of property.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Month, day and year when the business acquisition agreement was executed.

+ Details

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- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 159

-Paragraph 18

-Subparagraph f

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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.

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher AICPA

-Name Accounting Principles Board Opinion (APB)

-Number 18

-Paragraph 20

-Subparagraph a (1)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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.

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 323

-SubTopic 10

-Section 50

-Paragraph 3

-Subparagraph (a)(1)

-URI http://asc.fasb.org/extlink&oid=6382943&loc=d3e33918-111571

+ Details

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Investments In Unconsolidated Joint Ventures (Gale Kimball, L.L.C.) (Details) (Gale Kimball [Member], USD $)	0 Months Ended	3 Months Ended	9 Months Ended	12 Months Ended
	Jun. 15, 2006 sqft	Sep. 30, 2010	Sep. 30, 2010	Dec. 31, 2010
Gale Kimball [Member]
Percentage of interest in venture	8.33%
Date of acquisition	June 15,2006
Area of office property	175,000
Venture sale of real estate				$ 60,000,000
Management, leasing and other services fees		71,000	213,300
Share of gain on sale of real estate				1,600,000
Venture gain (loss) on sale of real estate				19,800,000
Distribution received				5,400,000
Payment of participation rights				$ 2,400,000