Shareholders' Equity (Schedule Of Dividends) (Details) - $ / shares	3 Months Ended	9 Months Ended
Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Class Of Stock [Line Items]
Common stock	$ 0.050	$ 0.050	$ 0.150	$ 0.150
Series B Preferred Stock [Member]
Class Of Stock [Line Items]
Cumulative Redeemable Preferred Stock	$ 0.453	$ 0.453	$ 1.359	$ 1.359
Dividend rate percentage			7.25%

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.

No definition available.

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- Definition

Aggregate dividends paid during the period for each share of common stock outstanding.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

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- Definition

The percentage rate used to calculate dividend payments on preferred stock.

+ References

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Aggregate dividends paid during the period for each share of preferred stock outstanding.

+ References

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