v3.7.0.1

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

3 Months Ended

Mar. 31, 2017

Mar. 31, 2016

Dec. 31, 2016

Dec. 31, 2015

Sep. 30, 2015

Fair Value Measurement [Domain]

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

Cash and Cash Equivalents, at Carrying Value

$ 36

$ 26

Restricted Cash and Cash Equivalents

130

127

Balance, beginning of period

399

$ (46)

Included in operating revenues

^[1]

113

(22)

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

^[2]

13

(14)

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

0

2

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

(26)

(4)

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]

7

0

Transfers out of Level 3

^[4],[5]

(150)

19

Balance, end of period

342

(65)

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

126

(36)

Cash and Cash Equivalents, at Carrying Value

243

$ 244

418

$ 906

Restricted Cash and Cash Equivalents

$ 177

$ 188

[1]	For power contracts and other power-related products, included on our Consolidated Condensed Statements of Operations.
[2]	For natural gas and power contracts, swaps and options, included on our Consolidated Condensed Statements of Operations.
[3]	There were $7 million and nil in losses transferred out of level 2 into level 3 for the three months ended March 31, 2017 and 2016, respectively, due to changes in market liquidity in various power markets.
[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, 2017 and 2016.
[5]	We had $150 million in gains and $(19) million in losses transferred out of level 3 into level 2 for the three months ended March 31, 2017 and 2016, 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
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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).

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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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