Consolidated Balance Sheets (Parenthetical) - $ / shares shares in Millions, $ / shares in Millions	Sep. 30, 2015	Dec. 31, 2014
Shareholders' equity:
Common stock, par value	$ 0	$ 0
Common stock, shares authorized	750	750
Common stock, shares issued	357	357
Common stock, shares outstanding	357	357

Face amount per share of no-par value 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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Reference 1: http://www.xbrl.org/2003/role/presentationRef

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