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Aggregate amount of intangible asset amortization recognized as expense during the period.

+ References

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-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
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The aggregate estimated amortization expense for succeeding fiscal years for intangible assets subject to amortization.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Statement of Financial Accounting Standard (FAS)
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The amount of amortization expense expected to be recognized for the remainder of the finite-lived intangible asset useful life after the fifth succeeding fiscal year.

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The amount of amortization expense expected to be recognized during the remainder of the current fiscal year.

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The amount of amortization expense expected to be recognized during year five of the five succeeding fiscal years.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
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The amount of amortization expense expected to be recognized during year four of the five succeeding fiscal years.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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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The amount of amortization expense expected to be recognized during year three of the five succeeding fiscal years.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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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The amount of amortization expense expected to be recognized during year two of the five succeeding fiscal years.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
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Deferred Leasing Costs and Acquisition-related Intangibles Assets and Liabilities, net (Details 1) (USD $) In Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010
Amortization for the period related to deferred leasing costs and acquisition-related intangibles
Amortization for the period related to deferred leasing costs and acquisition-related intangibles	$ 7,406	$ 3,295	$ 14,000	$ 5,990
Deferred Leasing Costs [Member]
Amortization for the period related to deferred leasing costs and acquisition-related intangibles
Amortization for the period related to deferred leasing costs and acquisition-related intangibles	3,970	2,968	7,738	5,673
Estimated annual amortization related to acquisition-related intangibles
Remaining 2011			8,946
2012			16,558
2013			14,751
2014			13,042
2015			9,859
Thereafter			24,021
Total			87,177
Net Above (Below)-Market Leases [Member]
Amortization for the period related to deferred leasing costs and acquisition-related intangibles
Amortization for the period related to deferred leasing costs and acquisition-related intangibles	745	60	1,398	32
Estimated annual amortization related to acquisition-related intangibles
Remaining 2011			706
2012			1,303
2013			1,062
2014			324
2015			(220)
Thereafter			(4,690)
Total			(1,515)
Leases Acquired In Place [Member]
Amortization for the period related to deferred leasing costs and acquisition-related intangibles
Amortization for the period related to deferred leasing costs and acquisition-related intangibles	2,686	267	4,859	285
Estimated annual amortization related to acquisition-related intangibles
Remaining 2011			6,165
2012			10,766
2013			8,682
2014			6,922
2015			3,991
Thereafter			6,353
Total			42,879
Leases Acquired In Place Above Market Ground Leases Adjustment [Member]
Amortization for the period related to deferred leasing costs and acquisition-related intangibles
Amortization for the period related to deferred leasing costs and acquisition-related intangibles	5	0	5	0
Estimated annual amortization related to acquisition-related intangibles
Remaining 2011			32
2012			63
2013			63
2014			63
2015			63
Thereafter			4,911
Total			$ 5,195