Revenues (Schedule Of Annual Future Base Rents Due To Be Received Under Non-Cancelable Operating Leases) (Details) (USD $)	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Revenues [Abstract]
2015	$ 106,034,000
2016	96,504,000
2017	85,264,000
2018	76,439,000
2019	63,524,000
Thereafter	301,207,000
Future rents due to be received	728,972,000
Expense recoveries	$ 32,100,000cdr_ExpenseRecoveries	$ 29,500,000cdr_ExpenseRecoveries	$ 26,500,000cdr_ExpenseRecoveries

Expense Recoveries

No definition available.

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- Definition

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

+ References

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

+ Details

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- Definition

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

+ References

+ Details

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- Definition

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

+ References

+ Details

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- Definition

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

+ References

+ Details

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- Definition

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

+ References

+ Details

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- Definition

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

+ References

+ Details

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