Share-Based Compensation And Other Compensation Arrangements (Schedule Of Stock Option Activity) (Details)2 $ / shares in Units, $ in Millions	12 Months Ended
Dec. 31, 2020 USD ($) $ / shares shares
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Shares, Outstanding at beginning of year \| shares	2,375,583
Shares, Exercised \| shares	(515,063)
Shares, Outstanding at end of year \| shares	1,860,520
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Roll Forward]
Weighted Average Exercise Price Per Share, Outstanding at beginning of year \| $ / shares	$ 74.79
Weighted Average Exercise Price Per Share, Exercised \| $ / shares	71.47
Weighted Average Exercise Price Per Share, Outstanding at end of year \| $ / shares	$ 75.71
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract]
Weighted Average Remaining Contractual Life (Years), Outstanding at end of year	1 year 7 months 24 days
Aggregate Intrinsic Value, Outstanding at end of year \| $	$ 257
Shares, Exercisable at end of year \| shares	1,860,520
Weighted Average Exercise Price Per Share, Exercisable at end of year \| $ / shares	$ 75.71
Weighted Average Remaining Contractual Life (Years), Exercisable at end of year	1 year 7 months 24 days
Aggregate Intrinsic Value, Exercisable at end of year \| $	$ 257

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The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

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Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

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Number of options outstanding, including both vested and non-vested options.

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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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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Weighted average price at which option holders acquired shares when converting their stock options into shares.

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Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of vested portions of options outstanding and currently exercisable.

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Weighted average remaining contractual term for vested portions of options outstanding and currently exercisable or convertible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Number of share options (or share units) exercised during the current period.

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