Common Shares And Stock-Based Awards Plans (Summary Of Stock-Based Awards) (Details) - $ / shares shares in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
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	593	525	467
Granted, shares or units	407	314	392
Vested, shares or units	(306)	(206)	(209)
Forfeited, shares or units	(99)	(40)	(125)
Non-vested shares outstanding, shares or units, ending balance	595	593	525
Non-vested outstanding, weighted-average grant date fair value, beginning balance	$ 27.47	$ 22.57	$ 21.59
Granted, weighted-average grant date fair value	29.44	31.56	22.71
Vested, weighted-average grant date fair value	27.25	21.84	21.07
Forfeited, weighted-average grant date fair value	27.52	24.21	21.85
Non-vested outstanding, weighted-average grant date fair value, ending balance	$ 28.93	$ 27.47	$ 22.57
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	346	227	306
Granted, shares or units	120	172	184
Forfeited, shares or units	(147)	(53)	(263)
Non-vested shares outstanding, shares or units, ending balance	319	346	227
Non-vested outstanding, weighted-average grant date fair value, beginning balance	$ 26.88	$ 21.43	$ 19.77
Granted, weighted-average grant date fair value	29.6	31.6	21.63
Forfeited, weighted-average grant date fair value	24.06	18.81	19.64
Non-vested outstanding, weighted-average grant date fair value, ending balance	$ 29.19	$ 26.88	$ 21.43

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=109197908&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
-Subparagraph (c)(2)(iii)(3)
-URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901

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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
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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-URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901

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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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-Topic 718
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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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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
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- Definition

The weighted average fair value of nonvested awards on equity-based plans excluding option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, revenue or profit achievement stock award plan) for which the employer is contingently obligated to issue equity instruments or transfer assets to an employee who has not yet satisfied service or performance criteria necessary to gain title to proceeds from the sale of the award or underlying shares or units.

+ References

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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.

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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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No definition available.

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