Rental Income (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014
Consolidated properties
Approximate future minimum rents to be received over the next five years and thereafter for non-cancelable operating leases
2015	$ 975,025
2016	964,428
2017	941,014
2018	879,727
2019	799,744
Thereafter	5,774,406
Total minimum lease payments	10,334,344
Unconsolidated properties
Approximate future minimum rents to be received over the next five years and thereafter for non-cancelable operating leases
2015	157,438
2016	157,514
2017	152,226
2018	146,605
2019	134,451
Thereafter	699,568
Total minimum lease payments	$ 1,447,802

Future minimum rental payments in aggregate as of the balance sheet date under operating leases.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 840

-SubTopic 20

-Section 50

-Paragraph 4

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6454179&loc=d3e41551-112718

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