v3.4.0.3

Assets and Liabilities with Recurring Fair Value Measurements (Textuals) (Details) - USD ($)
$ in Millions

3 Months Ended

Mar. 31, 2016

Mar. 31, 2015

Dec. 31, 2015

Dec. 31, 2014

Fair Value Measurement [Domain]

Fair Value, Assets, Liabilities and Stockholders' Equity Measured on Recurring Basis [Abstract]

Cash and Cash Equivalents, at Carrying Value

$ 216

$ 880

Restricted Cash and Cash Equivalents

160

203

Balance, beginning of period

(46)

$ 85

Included in operating revenues

^[1]

(22)

131

Fair Value, Assets Measured with Unobservable Inputs on Recurring Basis, Gain (Loss) Included In Fuel And Purchased Energy Expense

^[2]

(14)

3

Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases

2

2

Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Settlements

(4)

(10)

Fair Value, Liabilities, Level 1 to Level 2 Transfers, Amount

0

0

Fair Value, Liabilities, Level 2 to Level 1 Transfers, Amount

0

0

Transfers into level 3

^[3],[4]

0

1

Transfers out of Level 3

^[4],[5]

19

(7)

Balance, end of period

(65)

203

Fair Value, Assets Measured on Recurring Basis, Change in Unrealized Gain (Loss)

(36)

134

Cash and Cash Equivalents, at Carrying Value

244

$ 796

906

$ 717

Restricted Cash and Cash Equivalents

$ 184

$ 228

[1]	For power contracts and other power-related products, included on our Consolidated Condensed Statements of Operations.
[2]	For natural gas contracts, swaps and options, included on our Consolidated Condensed Statements of Operations.
[3]	There were no transfers out of level 2 into level 3 for the three months ended March 31, 2016. We had $1 million in losses transferred out of level 2 into level 3 for the three months ended March 31, 2015.
[4]	We transfer amounts among levels of the fair value hierarchy as of the end of each period. There were no transfers into or out of level 1 for each of the three months ended March 31, 2016 and 2015.
[5]	We had $(19) million in losses and $7 million in gains transferred out of level 3 into level 2 for the three months ended March 31, 2016 and 2015, respectively, due to changes in market liquidity in various power markets.

X

- Definition

Fair Value, Assets Measured with Unobservable Inputs on Recurring Basis, Gain (Loss) Included in Operating Revenue

+ References

No definition available.

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- Definition

Fair Value, Assets Measured with Unobservable Inputs on Recurring Basis, Gain (Loss) Included In Fuel And Purchased Energy Expense

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- Definition

Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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Amount of unrealized (holding) gain (loss) which is included in the statement of income (or changes in net assets) related to those assets still held at the reporting date for which fair value is measured on a recurring basis using significant unobservable inputs (Level 3).

+ References

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Amount of transfers of liabilities measured on a recurring basis out of Level 1 of the fair value hierarchy into Level 2.

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Amount of transfers of liabilities measured on a recurring basis out of Level 2 of the fair value hierarchy into Level 1.

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Amount of purchases of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Amount of settlement of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Amount of transfer of financial instrument classified as an asset into level 3 of the fair value hierarchy.

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The carrying amounts of cash and cash equivalent items which are restricted as to withdrawal or usage. Restrictions may include legally restricted deposits held as compensating balances against borrowing arrangements, contracts entered into with others, or entity statements of intention with regard to particular deposits; however, time deposits and short-term certificates of deposit are not generally included in legally restricted deposits. Excludes compensating balance arrangements that are not agreements which legally restrict the use of cash amounts shown on the balance sheet. This element is for unclassified presentations; for classified presentations there is a separate and distinct element.

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