Consolidated Balance Sheets Consolidated Balance Sheets Parenthetical (USD $) In Millions, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Common stock, par value	$ 0us-gaap_CommonStockNoParValue	$ 0us-gaap_CommonStockNoParValue
Common stock, shares authorized	750us-gaap_CommonStockSharesAuthorized	750us-gaap_CommonStockSharesAuthorized
Common stock, shares issued	357us-gaap_CommonStockSharesIssued	357us-gaap_CommonStockSharesIssued
Common stock, shares outstanding	357us-gaap_CommonStockSharesOutstanding	357us-gaap_CommonStockSharesOutstanding

Face amount per share of no-par value common stock.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

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-Name Accounting Standards Codification

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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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- Definition

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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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

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Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

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Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

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-Section S99

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Reference 4: http://www.xbrl.org/2003/role/presentationRef

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