This element represents the length of revolving working capital loan and letter of credit facility.

No definition available.

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- Definition

Length of term loan facility (in years).

+ References

No definition available.

+ Details

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- Definition

Represents the number of peaking facilities to be constructed as per the contract.

+ References

No definition available.

+ Details

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Data Type:	xbrli:integerItemType
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- Definition

The generation capacity of the entity's power generation facilities as of the balance sheet date, expressed in megawatts.

+ References

No definition available.

+ Details

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Period Type:	instant

- Definition

Represents the power generation capacity of the peaking facility to be constructed as per the contract.

+ References

No definition available.

+ Details

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- Definition

Working Capital Facility, Amount Drawn

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)(1)
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- Definition

This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized.

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- Definition

The amount by which the fair value of an investment is less than the amortized cost basis or carrying amount of that investment at the balance sheet date and the decline in fair value is deemed to be other than temporary, before considering whether or not such amount is recognized in earnings or other comprehensive income.

+ References

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Balance Type:	debit
Period Type:	duration

- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Balance Type:	credit
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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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Investments Accounted for by the Equity Method and Variable Interest Entities Investments Accounted for by the Equity Method and Variable Interest Entities (VIEs - Details 2) $ in Millions	1 Months Ended		12 Months Ended
	Apr. 30, 2009	Dec. 31, 2008	Dec. 31, 2016 USD ($) MW facility	Dec. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)	Sep. 17, 2013 USD ($)	Dec. 31, 2009 MW
Schedule of Equity Method Investments [Line Items]
Long-term Debt			$ 19,406	$ 19,620
Working Capital Facility, Amount Drawn			14
Equity investments in affiliates			1,120	1,045
Other than Temporary Impairment Losses, Investments			$ 268	56	$ 0
GenConn Energy LLC (a)
Schedule of Equity Method Investments [Line Items]
Equity Method Investment, Ownership Percentage			50.00%
Number of Peaking Facilities to be Constructed \| facility			2
Power Generation Capacity of Peaking Facility to be Constructed \| MW			190
Equity investments in affiliates			$ 106
Sherbino I Wind Farm LLC
Schedule of Equity Method Investments [Line Items]
Equity Method Investment, Ownership Percentage							50.00%
Power Generation Capacity, Megawatts \| MW							150
Other than Temporary Impairment Losses, Investments			70
GenConn Working Capital Facility [Member] \| GenConn Energy LLC (a)
Schedule of Equity Method Investments [Line Items]
Length of Revolving Working Capital, Loan and Letter of Credit Facility	5 years
Non Recourse Debt [Member]
Schedule of Equity Method Investments [Line Items]
Long-term Debt			11,620	$ 11,036
Non Recourse Debt [Member] \| GenConn Facility [Member] \| GenConn Energy LLC (a)
Schedule of Equity Method Investments [Line Items]
Long-term Debt			212			$ 237
Debt Instrument, Interest Rate, Stated Percentage						4.73%
Non Recourse Debt [Member] \| GenConn Working Capital Facility [Member] \| GenConn Energy LLC (a)
Schedule of Equity Method Investments [Line Items]
Long-term Debt						$ 35
Debt Instrument, Interest Rate, Stated Percentage						1.875%
Non Recourse Debt [Member] \| Sherbino I Wind Farm LLC Term Loan Facility [Member] \| Sherbino I Wind Farm LLC
Schedule of Equity Method Investments [Line Items]
Length of Term Loan Facility		15 years
Long-term Line of Credit			$ 72