Deferred Costs, Acquired Lease Intangibles and Goodwill - Acquired Leases (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Acquired Finite-Lived Intangible Assets [Line Items]
Acquired below-market ground lease, Gross Amount	$ 396,916us-gaap_GroundLeasesGross	$ 396,916us-gaap_GroundLeasesGross
Acquired below-market ground lease, Accumulated Amortization	(7,151)	(5,029)
Acquired below-market leases, Gross Amount	(168,372)us-gaap_BelowMarketLeaseGross	(169,805)us-gaap_BelowMarketLeaseGross
Acquired below-market leases, Accumulated Amortization	38,636	30,946
Acquired in-place lease value and deferred leasing costs [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible assets, Gross Amount	300,725	304,916
Finite-lived intangible assets, Accumulated Amortization	(92,680)	(83,540)
Acquired above-market leases [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible assets, Gross Amount	84,213	84,633
Finite-lived intangible assets, Accumulated Amortization	$ (19,172)	$ (15,761)

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Amount of accumulated amortization of leases acquired as part of a real property acquisition at below market lease rate with a finite life.

+ References

No definition available.

+ Details

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- Definition

Amount before amortization of leases acquired as part of a real property acquisition at below market lease rate with a finite life.

+ References

No definition available.

+ Details

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- Definition

Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 30

-Section 50

-Paragraph 2

-Subparagraph (a)(1)

-URI http://asc.fasb.org/extlink&oid=26713463&loc=d3e16323-109275

+ Details

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- Definition

Amount before amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

+ Details

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- Definition

Accumulated amortization on long-term land leases capitalized as part of real property.

+ References

No definition available.

+ Details

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- Definition

Gross long-term land leases capitalized as part of real property.

+ References

No definition available.

+ Details

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- Details

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- Details

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