Share-Based Compensation (Schedule Of Restricted Stock Unit Activity) (Details) shares in Thousands	12 Months Ended
Dec. 31, 2020 $ / shares shares
Restricted stock units (RSU's)
Number of Units
Nonvested, at beginning of year (in shares) \| shares	258
Granted (in shares) \| shares	65
Vested (in shares) \| shares	(94)
Forfeited (in shares) \| shares	(11)
Nonvested, at end of year (in shares) \| shares	218
Weighted Average Grant-Date Fair Value
Weighted average grant date fair value, beginning of year (in USD per share) \| $ / shares	$ 150.50
Weighted average grant date fair value, granted (in USD per share) \| $ / shares	291.30
Weighted average grant date fair value, vested (in USD per share) \| $ / shares	124.60
Weighted average grant date fair value, forfeited (in USD per share) \| $ / shares	178.95
Weighted average grant date fair value, end of year (in USD per share) \| $ / shares	$ 202.47
Restricted stock units expected to vest reduced for estimated forfeitures
Number of Units
Nonvested, at end of year (in shares) \| shares	208
Weighted Average Grant-Date Fair Value
Weighted average grant date fair value, end of year (in USD per share) \| $ / shares	$ 201.64

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

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(iv)(3)
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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.

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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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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.

+ References

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

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-Publisher FASB
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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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