Future Minimum Lease Receipts (Schedule Of Future Minimum Base Rentals On Non-Cancelable Office And Ground Operating Leases) (Details) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2014
Operating Leases, Future Minimum Payments Receivable [Abstract]
2015	$ 369,228
2016	331,731
2017	280,913
2018	226,199
2019	178,563
Thereafter	445,366
Total future minimum base rentals	$ 1,832,000

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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- 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.

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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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