Organization and Summary of Significant Accounting Policies (Details) (USD $) In Millions	3 Months Ended	6 Months Ended
Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010	Dec. 31, 2010
Excise taxes
Excise taxes	$ 76	$ 81	$ 149	$ 164
Consolidation of variable interest entities
Cumulative effect of change in accounting principle			0
Miscellaneous other property and investments	12		12		12
Other assets and deferred debits	1		1		1
Accounts payable	0		0		5
VIE - exposure to loss from capital lease agreements	$ 7.5		$ 7.5
VIE - activity with VIE related to lease payments	$1 million	$1 million	$1 million	$1 million

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- Definition

The carrying amount of the variable interest entity's liabilities, included in accounts payable, consolidated into the statement of financial position. In general, a VIE is a corporation, partnership, trust, or any other legal structure used for business purposes that either (a) does not have equity investors with voting rights or (b) has equity investors that do not provide sufficient financial resources for the entity to support its activities. A VIE often holds financial assets, including loans or receivables, real estate or other property. A VIE may be essentially passive or it may engage in research and development or other activities on behalf of another company.

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- Definition

The carrying amount of the variable interest entity's assets, included in miscellaneous other property and investments, consolidated into the statement of financial position. In general, a VIE is a corporation, partnership, trust, or any other legal structure used for business purposes that either (a) does not have equity investors with voting rights or (b) has equity investors that do not provide sufficient financial resources for the entity to support its activities. A VIE often holds financial assets, including loans or receivables, real estate or other property. A VIE may be essentially passive or it may engage in research and development or other activities on behalf of another company.

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- Definition

The carrying amount of the variable interest entity's assets, included in other assets and deferred debits, consolidated into the statement of financial position. In general, a VIE is a corporation, partnership, trust, or any other legal structure used for business purposes that either (a) does not have equity investors with voting rights or (b) has equity investors that do not provide sufficient financial resources for the entity to support its activities. A VIE often holds financial assets, including loans or receivables, real estate or other property. A VIE may be essentially passive or it may engage in research and development or other activities on behalf of another company.

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- Definition

The reporting entity's maximum amount of exposure to loss as a result of its involvement with the Variable Interest Entity (VIE).

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- Definition

Cumulative effect of initial adoption of new accounting principle on beginning retained earnings, net of tax. This element can be used, generally, for the adjustment to retained earnings of a new accounting principle.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 154
-Paragraph 17, 18

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- Definition

The excise taxes collected by a public utility and reported in revenues if the amount of excise taxes is equal to 1 percent or more of such total.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 03
-Paragraph 1
-Subparagraph e
-Article 5

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- Definition

Amount of income, expense, purchases, sales, or other measure of activity between the registrant and the VIE or potential VIE for all periods presented. If it is not practicable to present that information for prior periods that are presented in the first set of financial statements for which this requirement applies, the information for those prior periods is not required. In general, a VIE is a corporation, partnership, trust, or any other legal structure used for business purposes that either (a) does not have equity investors with voting rights or (b) has equity investors that do not provide sufficient financial resources for the entity to support its activities. A VIE often holds financial assets, including loans or receivables, real estate or other property. A VIE may be essentially passive or it may engage in research and development or other activities on behalf of another company.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name FASB Interpretation (FIN)
-Number 46R
-Paragraph 26
-Subparagraph d

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name FASB Staff Position (FSP)
-Number FAS140-4 and FIN46(R)-8
-Paragraph C8
-Subparagraph d

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