Unaudited Condensed Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Billions	Mar. 31, 2021	Dec. 31, 2020
Statement of Financial Position [Abstract]
PROPERTY AND EQUIPMENT, accumulated depreciation	$ 1.7	$ 1.7
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock authorized (in shares)	1,500,000,000	1,500,000,000
Common stock issued (in shares)	102,562,149	102,562,149
Treasury stock (in shares)	22,088,073	19,078,620

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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Face amount or stated value per share of common stock.

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

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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.

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Number of common and preferred shares that were previously issued and that were repurchased by the issuing entity and held in treasury on the financial statement date. This stock has no voting rights and receives no dividends.

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