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Share-Based Compensation (Summary Of Vested And Unvested RSU) (Details) - Restricted Stock And Restricted Stock Unit [Member] - $ / shares	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Outstanding shares, Beginning balance (in shares)	169,000	271,000	263,250
Granted, shares (in shares)	0	0	95,750
Vested, shares (in shares)	0	(82,000)	(78,500)
Forfeited/canceled, shares (in shares)	(8,000)	(20,000)	(9,500)
Expired, shares (in shares)	(85,750)	0	0
Outstanding shares, Ending balance (in shares)	75,250	169,000	271,000
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Roll Forward]
Outstanding, Weighted-Average Fair Value per Share, Beginning (in dollars per share)	$ 53.66	$ 51.09	$ 45.94
Granted, Weighted-Average Fair Value per Share (in dollars per share)	0.00	0.00	53.49
Vested, Weighted-Average Fair Value per Share (in dollars per share)	0.00	45.17	36.82
Forfeited/Canceled, Weighted-Average Fair Value per Share (in dollars per share)	53.49	53.62	50.46
Expired, Weighted-Average Fair Value per Share (in dollars per share)	53.80	0.00	0.00
Outstanding, Weighted-Average Fair Value per Share, Ending (in dollars per share)	$ 53.51	$ 53.66	$ 51.09

X

- Definition

Share-based Compensation Arrangements by Share-based Payment Award, Non-Option Equity Instruments, Expirations in Period, Weighted Average Grant Date Fair Value

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No definition available.

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

+ References

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-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.

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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).

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- Definition

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).

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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.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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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.

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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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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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Number of shares under non-option equity instrument agreements for which rights to exercise lapsed.

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