Incentive Plans (Summary Of Activity Of Executive Continuity And Restricted Stock Award Program) (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]
Shares/units, outstanding	5,799,884	5,950,130	5,857,733
Shares/units, granted	1,751,235	2,163,912	2,617,982
Shares/units, shares issued	(1,588,642)	(1,876,134)	(2,316,085)
Shares/units, forfeited	(196,000)	(438,024)	(209,500)
Shares/Units, outstanding	5,766,477	5,799,884	5,950,130
Weighted average grant date fair value, outstanding	$ 36.17	$ 35.89	$ 38.69
Weighted average grant date fair value, granted	62.97	51.78	37.26
Weighted average grant date fair value, shares issued	53.67	51	43.82
Weighted average grant date fair value, forfeited	56.57	45.96	43.61
Weighted average grant date fair value, outstanding	$ 38.79	$ 36.17	$ 35.89
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares/units, outstanding	166,300	169,331	120,368
Shares/units, granted	66,100	63,319	117,881
Shares/units, shares issued	(100,289)	(59,650)	(59,418)
Shares/units, forfeited	0	(6,700)	(9,500)
Shares/Units, outstanding	132,111	166,300	169,331
Weighted average grant date fair value, outstanding	$ 48.63	$ 45.34	$ 48.24
Weighted average grant date fair value, granted	51.43	57.24	42.81
Weighted average grant date fair value, shares issued	48.44	47.90	47.14
Weighted average grant date fair value, forfeited	0	53.53	39.36
Weighted average grant date fair value, outstanding	$ 50.17	$ 48.63	$ 45.34

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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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)
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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
-Subparagraph (c)(2)(iii)(1)
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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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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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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
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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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- 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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