Stockholders' Equity - Common Stock (Details) - $ / shares	Sep. 30, 2021	Dec. 31, 2020
Equity [Abstract]
Common stock, par value ( in USD per share)	$ 0.001	$ 0.001
Common stock authorized (in shares)	9,000,000,000	9,000,000,000
Common stock issued (in shares)	4,020,000,000	4,176,000,000
Common stock outstanding (in shares)	4,018,000,000	4,173,000,000
Common stock reserved for issuance (in shares)	252,000,000

Aggregate number of common shares reserved for future issuance.

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Face amount or stated value per share of common stock.

+ References

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The maximum number of common shares permitted to be issued by an entity's charter and bylaws.

+ References

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Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation.

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-Topic 505
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