Schedule I Condensed Balance Sheets (Paranthetical) (USD $) In Millions, except Per Share data, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Condensed Financial Statements, Captions [Line Items]
Common stock, par value	$ 0us-gaap_CommonStockNoParValue	$ 0us-gaap_CommonStockNoParValue
Common stock, shares authorized	115us-gaap_CommonStockSharesAuthorized	115us-gaap_CommonStockSharesAuthorized
Common stock, shares issued	77us-gaap_CommonStockSharesIssued	77us-gaap_CommonStockSharesIssued
Common stock, shares outstanding	77us-gaap_CommonStockSharesOutstanding	77us-gaap_CommonStockSharesOutstanding
Parent [Member]
Condensed Financial Statements, Captions [Line Items]
Common stock, par value	$ 0	$ 0
Common stock, shares authorized	115	115
Common stock, shares issued	77	77
Common stock, shares outstanding	77	77

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

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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

-Article 3

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

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-Name Accounting Standards Codification

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

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

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Reference 5: http://www.xbrl.org/2003/role/presentationRef

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