Basis of Presentation (Details) (USD $) In Millions, except Share data, unless otherwise specified	3 Months Ended	9 Months Ended
Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011	Dec. 31, 2011
Basis of Presentation [Abstract]
Other Comprehensive Income	$ 0	$ 0	$ 0	$ 0
Number of Retail Customers	829,280		829,280
Other regulatory liabilities					6
Pension and other postretirement benefit expense			22	3
Senate Bill 408 deferrals, net				$ (5)

Net of tax amount of other comprehensive income (loss) attributable to the parent entity.

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+ Details

- Definition

The amount of pension and other (such as medical, dental and life insurance) postretirement benefit costs recognized during the period for (1) defined benefit plans (periodic benefit costs include the following components: service cost, interest cost, expected return on plan assets, gain (loss) on assets, prior service cost or credit, transition asset or obligation, and gain (loss) due to settlements or curtailments) and for (2) defined contribution plans (to the extent that a plan's defined contributions to an individual's account are to be made for periods in which that individual renders services, the net cost for a period is the contribution called for in that period; if a plan calls for contributions for periods after an individual retires or terminates, the estimated cost is accrued during the employee's service period).

+ References

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