Rental Income Schedule of Future Minimum Payments Receivable for Operating Leases (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014
Operating Leases, Future Minimum Payments Receivable [Abstract]
2014	$ 401,615
2015	369,166
2016	341,395
2017	302,143
2018	275,509
Thereafter	1,298,926
Total Future Minimum Payments Receivable for Operating Leases	$ 2,988,754

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

+ Details

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- Definition

Future rental payments receivable within one year of the balance sheet date under an operating lease.

+ References

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- Definition

Future rental payments receivable within the fifth year from the balance sheet date under an operating lease.

+ References

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- Definition

Future rental payments receivable within the fourth year from the balance sheet date under an operating lease.

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- Definition

Future rental payments receivable within the third year from the balance sheet date under an operating lease.

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- Definition

Future rental payments receivable within the second year from the balance sheet date under an operating lease.

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- Definition

Future minimum lease payments receivable under operating leases for periods greater than five years following the balance sheet date.

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