Number of floors real estate

No definition available.

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- Definition

Number of Joint Venture Partners

+ References

No definition available.

+ Details

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- Definition

Partners Joint Venture Ownership Percentage

+ References

No definition available.

+ Details

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- Definition

Carrying amount of the equity interests owned by noncontrolling partners of a limited partnership included in the entity's consolidated financial statements.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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- Details

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- Definition

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

+ References

No definition available.

+ Details

Name:	us-gaap_MinorityInterestOwnershipPercentageByNoncontrollingOwners
Namespace Prefix:	us-gaap_
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- Definition

Net rentable area for properties owned.

+ References

No definition available.

+ Details

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Balance Type:	na
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- Definition

Increase in noncontrolling interest balance because of a business combination that occurred during the period.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
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- Definition

The cash outflow from the acquisition of real estate intended to generate income for the owner; excludes land acquired for use by the owner.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 13

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3213-108585

+ Details

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Noncontrolling Interests (Property Partnerships) (Narrative) (Details) (USD $)	9 Months Ended			0 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Dec. 31, 2012	Mar. 26, 2013 Transbay Tower [Member] floor sqft	Feb. 26, 2013 Transbay Tower [Member]	Feb. 07, 2013 Transbay Tower [Member]	May 31, 2013 767 Fifth Avenue (The GM Building) [Member] partners sqft
Noncontrolling Interest [Line Items]
Property partnerships	$ 481,629,000		$ (1,964,000)
Partners Joint Venture Ownership Percentage					5.00%	50.00%
Ownership Percentage				95.00%	95.00%		40.00%
Number of floors real estate				60
Net Rentable Area				1,400,000			1,800,000
Payments to Acquire Land				192,000,000
Number of Joint Venture Partners							2
Noncontrolling interest recorded upon consolidation	$ 480,861,000	$ 0					$ 480,861,000