Share-Based Compensation - Summary Of Stock Option Activity Under All Stock Plans (Details) shares in Millions	12 Months Ended
Dec. 31, 2020 $ / shares shares
Number Outstanding
Beginning balance (shares) \| shares	5.4
Options granted (shares) \| shares	0.5
Options exercised (shares) \| shares	(1.3)
Options forfeited/expired (shares) \| shares	(0.1)
Ending balance (shares) \| shares	4.5
Weighted Average Exercise Price Per Share
Beginning balance (usd per share) \| $ / shares	$ 246.64
Options granted (usd per share) \| $ / shares	624.45
Options exercised (usd per share) \| $ / shares	179.67
Options forfeited/expired (usd per share) \| $ / shares	490.77
Ending balance (usd per share) \| $ / shares	$ 305.06

Share-based Compensation Arrangement by Share-based Payment Award, Options, Weighted Average Exercise Price [Abstract]

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- Definition

Number of options or other stock instruments for which the right to exercise has lapsed under the terms of the plan agreements.

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Net number of share options (or share units) granted during the period.

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

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-Name Accounting Standards Codification
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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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Weighted average price at which grantees could have acquired the underlying shares with respect to stock options of the plan that expired.

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Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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

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