Consolidated Balance Sheets (Parenthetical) - USD ($) shares in Thousands, $ in Millions	Jun. 30, 2020	Dec. 31, 2019
Statement of Financial Position [Abstract]
Held-to-maturity, fair value	$ 691	$ 597
Preferred stock, shares authorized (in shares)	4,400	4,400
Common stock, par value (in dollars per share)	$ 0.001	$ 0.001
Common stock, shares authorized (in shares)	350,000	350,000
Common stock, shares issued (in shares)	163,978	165,057
Common stock, outstanding shares (in shares)	163,978	165,057

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 shares of common stock outstanding. Common stock represent the ownership interest in a corporation.

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Fair value of investment in debt security measured at amortized cost (held-to-maturity).

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The maximum number of nonredeemable preferred shares (or preferred stock redeemable solely at the option of the issuer) permitted to be issued by an entity's charter and bylaws.

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