Disclosure Of Fair Value Of Assets And Liabilities (Schedule Of Valuation Techniques And Significant Unobservable Inputs) (Details) - Level 3 [Member] - Discounted Cash Flow [Member]	12 Months Ended
Dec. 31, 2015 USD ($)
Discount Rate [Member] \| Suburban [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair value	$ 404,863,000
Discount Rate [Member] \| Suburban [Member] \| Minimum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Discount rate	8.00%
Discount Rate [Member] \| Suburban [Member] \| Maximum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Discount rate	15.00%
Discount Rate [Member] \| Central Business District [Member] \| Minimum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Discount rate	6.00%
Discount Rate [Member] \| Central Business District [Member] \| Maximum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Discount rate	9.50%
Exit Capitalization Rate [Member] \| Suburban [Member] \| Minimum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Discount rate	7.50%
Exit Capitalization Rate [Member] \| Suburban [Member] \| Maximum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Discount rate	9.00%
Exit Capitalization Rate [Member] \| Central Business District [Member] \| Minimum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Discount rate	5.00%
Exit Capitalization Rate [Member] \| Central Business District [Member] \| Maximum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Discount rate	5.75%

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Interest rate used to find the present value of an amount to be paid or received in the future as an input to measure fair value. For example, but not limited to, weighted average cost of capital (WACC), cost of capital, cost of equity and cost of debt.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (bbb)
-URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258

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