Common Shares And Stock-Based Awards Plans (Summary Of Stock-Based Awards) (Details) - $ / shares shares in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Non-vested shares outstanding, shares or units, beginning balance	595	593	525
Granted, shares or units	632	407	314
Vested, shares or units	(254)	(306)	(206)
Forfeited, shares or units	(80)	(99)	(40)
Non-vested shares outstanding, shares or units, ending balance	893	595	593
Non-vested outstanding, weighted-average grant date fair value, beginning balance	$ 28.93	$ 27.47	$ 22.57
Granted, weighted-average grant date fair value	27.36	29.44	31.56
Vested, weighted-average grant date fair value	28.09	27.25	21.84
Forfeited, weighted-average grant date fair value	28.97	27.52	24.21
Non-vested outstanding, weighted-average grant date fair value, ending balance	$ 28.06	$ 28.93	$ 27.47
Performance-Based Restricted Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Non-vested shares outstanding, shares or units, beginning balance	319	346	227
Granted, shares or units	198	120	172
Vested, shares or units	(57)
Forfeited, shares or units	(76)	(147)	(53)
Non-vested shares outstanding, shares or units, ending balance	384	319	346
Non-vested outstanding, weighted-average grant date fair value, beginning balance	$ 29.19	$ 26.88	$ 21.43
Granted, weighted-average grant date fair value	27.45	29.60	31.60
Vested, weighted-average grant date fair value	31.40
Forfeited, weighted-average grant date fair value	21.23	24.06	18.81
Non-vested outstanding, weighted-average grant date fair value, ending balance	$ 28.89	$ 29.19	$ 26.88

The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

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 (c)(1)(iv)(3)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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- Definition

Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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-Paragraph 2
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The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

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-Publisher FASB
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- Definition

The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

+ References

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- Definition

Per share or unit weighted-average fair value of nonvested award under share-based payment arrangement. Excludes share and unit options.

+ References

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-Publisher FASB
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- Definition

The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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-Publisher FASB
-Name Accounting Standards Codification
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- Definition

The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

+ References

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-Publisher FASB
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- Definition

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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