Shareholders' Equity (Schedule Of Dividends) (Details) - $ / shares	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Class Of Stock [Line Items]
Common stock	$ 0.200	$ 0.200	$ 0.200
Cumulative Redeemable Preferred Stock	$ 1.812	$ 1.812	$ 1.812
Series B [Member]
Class Of Stock [Line Items]
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

No definition available.

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- Definition

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

+ References

No definition available.

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