Incentive Program (Summary Of Restricted Stock And Units Outstanding) (Details) shares in Thousands	12 Months Ended
Dec. 31, 2020 $ / shares shares
Share-based Payment Arrangement [Abstract]
Issued and outstanding at January 1, Restricted stock, Shares \| shares	39,628
Awards issued in 2020, Shares \| shares	9,030
Vested, Shares \| shares	(8,990)
Forfeited, Shares \| shares	(83)
Issued and outstanding at December 31, Restricted stock, Shares \| shares	39,585
Issued and outstanding at January 1, Weighted Average Grant-Date Fair Value per Share \| $ / shares	$ 84.50
Awards issued in 2020, Weighted Average Grant-Date Fair Value per Share \| $ / shares	68.95
Vested, Weighted Average Grant-Date Fair Value per Share \| $ / shares	86.84
Forfeited, Weighted Average Grant-Date Fair Value per Share \| $ / shares	82.04
Issued and outstanding at December 31, Weighted Average Grant-Date Fair Value per Share \| $ / shares	$ 80.43

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

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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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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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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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Issued And Outstanding Restricted Stock.

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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

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

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