Incentive Program (Summary Of Restricted Stock And Units Outstanding) (Details) (Restricted Stock [Member], USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended
Dec. 31, 2013
Restricted Stock [Member]
Issued and outstanding at January 1, Restricted stock, Shares	46,451
2012 award issued in 2013, Shares	10,016
Vested, Shares	(11,068)
Forfeited, Shares	(192)
Issued and outstanding at December 31, Restricted stock, Shares	45,207
Issued and outstanding at January 1, Weighted Average Grant-Date Fair Value per Share	$ 73.94
2012 award issued in 2013, Weighted Average Grant-Date Fair Value per Share	$ 87.24
Vested, Weighted Average Grant-Date Fair Value per Share	$ 68.15
Forfeited, Weighted Average Grant-Date Fair Value per Share	$ 77.22
Issued and outstanding at December 31, Weighted Average Grant-Date Fair Value per Share	$ 78.29

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

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-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=6415400&loc=d3e5070-113901

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Period Type:	duration

- 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

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-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=6415400&loc=d3e5070-113901

+ Details

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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

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(2)(i)-(ii)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

+ Details

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Period Type:	instant

- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

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

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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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

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

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

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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Balance Type:	na
Period Type:	duration

- Definition

Issued And Outstanding Restricted Stock.

+ References

No definition available.

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- Definition

Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Grants In Period Prior Year Awards Issued Granted In Current Year

+ References

No definition available.

+ Details

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Period Type:	duration

- Definition

Weighted Average Fair Value Of Restricted Stock And Restricted Stock Units At Grant Date

+ References

No definition available.

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