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Summary Of Significant Accounting Policies (Schedule Of Assumptions For Valuing Stock Options Granted) (Details) - $ / shares	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Dividend yield	2.27%	1.90%
Weighted average volatility percentage	38.30%	38.30%
Weighted average risk-free interest rate	2.80%	1.80%
Weighted average exercise price at date of grant (also weighted average market price at date of grant):	$ 19.35	$ 15.65	$ 0.00
Officers
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Holding period (years):	5 years	5 years
Weighted average exercise price at date of grant (also weighted average market price at date of grant):	$ 19.35	$ 15.65
Management
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Holding period (years):	5 years	5 years
Weighted average exercise price at date of grant (also weighted average market price at date of grant):	$ 19.35	$ 15.65

X

- Definition

The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (f)(2)(iii)
-URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901

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- Definition

The risk-free interest rate assumption that is used in valuing an option on its own shares.

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-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Weighted average expected volatility rate of share-based compensation awards.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (f)(2)(ii)
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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.

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Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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- Definition

Expected term of share-based compensation awards, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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