Fair Value Measurements (Schedule Of Quantitative Information Regarding Level 3 Assets Measured At Fair Value On Non-recurring Basis) (Details)	9 Months Ended
Sep. 30, 2017 USD ($)
Fair Value Inputs Assets Quantitative Information [Line Items]
Real estate held for sale	$ 1,815,000
Nonrecurring Basis [Member]
Fair Value Inputs Assets Quantitative Information [Line Items]
Real estate held for sale	1,815,000
Nonrecurring Basis [Member] \| Level 3 [Member]
Fair Value Inputs Assets Quantitative Information [Line Items]
Real estate held for sale	1,815,000
Nonrecurring Basis [Member] \| Level 3 [Member] \| Assets [Member] \| Vacant Commercial Property [Member] \| Discounted Cash Flow Valuation Technique [Member]
Fair Value Inputs Assets Quantitative Information [Line Items]
Real estate held for sale	$ 1,815,000
Capitalization rate	9.00%
Discount rate	13.00%

Amount classified as assets attributable to disposal group held for sale or disposed of.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (e)
-URI http://asc.fasb.org/extlink&oid=64862545&loc=d3e2941-110230

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 205
-SubTopic 20
-Section 45
-Paragraph 10
-URI http://asc.fasb.org/extlink&oid=65878427&loc=d3e1107-107759

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 205
-SubTopic 20
-Section 50
-Paragraph 5B
-Subparagraph (e)
-URI http://asc.fasb.org/extlink&oid=64827811&loc=SL51721673-107760

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 205
-SubTopic 20
-Section 45
-Paragraph 11
-URI http://asc.fasb.org/extlink&oid=65878427&loc=SL51721533-107759

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Ratio of the net operating income produced by an asset and its capital cost (original prices paid to buy the asset), used as an input to measure fair value.

+ 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=66048111&loc=d3e19207-110258

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