Stock-Based Compensation - Acquisitions (Details) $ / shares in Units, shares in Millions, $ in Millions	Jul. 09, 2019 USD ($) shares	Dec. 31, 2020 $ / shares shares
Red Hat, Inc. \| Stock Awards
Share-based Compensation Arrangement by Share-based Payment Award
Stock awards issued in connection with the acquisition (in shares)	6.4
Stock awards issued in connection with the acquisition \| $	$ 845
Share conversion ratio	1.35
Stock awards outstanding (in shares)		2.1
Stock awards weighted-average grant price (in dollars per share) \| $ / shares		$ 140
Various other acquisition transactions \| Stock Options
Share-based Compensation Arrangement by Share-based Payment Award
Additional stock options outstanding in connection with acquisitions (in shares)		0.1
Additional options outstanding, weighted-average exercise price (in dollars per share) \| $ / shares		$ 44

Ratio applied to the conversion of stock.

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The number of additional shares reserved for issuance under stock option agreements in connection with various acquisition transactions.

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

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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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Number of shares of stock issued during the period pursuant to acquisitions.

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