v3.7.0.1

Fair Value Measurements (Significant Unobservable Inputs Used in Valuation of Contracts) (Details) - Level 3 [Member] $ in Millions | 6 Months Ended
--- | ---
Jun. 30, 2017 USD ($) $ / MWh $ / MMBTU
Forward Contracts - Power [Member] | Discounted Cash Flow Member] | Minimum [Member] |
Fair Value Inputs, Assets, Quantitative Information [Line Items] |
Forward price (in dollars per energy unit) | $ / MWh | 0
Forward Contracts - Power [Member] | Discounted Cash Flow Member] | Maximum [Member] |
Fair Value Inputs, Assets, Quantitative Information [Line Items] |
Forward price (in dollars per energy unit) | $ / MWh | 92
Forward contracts - Gas [Member] | Discounted Cash Flow Member] | Minimum [Member] |
Fair Value Inputs, Assets, Quantitative Information [Line Items] |
Forward price (in dollars per energy unit) | $ / MMBTU | 2
Forward contracts - Gas [Member] | Discounted Cash Flow Member] | Maximum [Member] |
Fair Value Inputs, Assets, Quantitative Information [Line Items] |
Forward price (in dollars per energy unit) | $ / MMBTU | 6
Option Contracts, Power [Member] | Option Models [Member] | Minimum [Member] |
Fair Value Inputs, Assets, Quantitative Information [Line Items] |
Implied volatilities (percent) | 8.00%
Implied correlations (percent) | 1.00%
Option Contracts, Power [Member] | Option Models [Member] | Maximum [Member] |
Fair Value Inputs, Assets, Quantitative Information [Line Items] |
Implied volatilities (percent) | 246.00%
Implied correlations (percent) | 100.00%
Option Contracts, Primarily Gas [Member] | Option Models [Member] | Minimum [Member] |
Fair Value Inputs, Assets, Quantitative Information [Line Items] |
Implied volatilities (percent) | 0.00%
Implied correlations (percent) | 1.00%
Option Contracts, Primarily Gas [Member] | Option Models [Member] | Maximum [Member] |
Fair Value Inputs, Assets, Quantitative Information [Line Items] |
Implied volatilities (percent) | 102.00%
Implied correlations (percent) | 100.00%
Full Requirements and Unit Contingent Contracts [Member] | Discounted Cash Flow Member] | Minimum [Member] |
Fair Value Inputs, Assets, Quantitative Information [Line Items] |
Forward price (in dollars per energy unit) | $ / MWh | (19.69)
Customer migration rate (percent) | 0.00%
Full Requirements and Unit Contingent Contracts [Member] | Discounted Cash Flow Member] | Maximum [Member] |
Fair Value Inputs, Assets, Quantitative Information [Line Items] |
Forward price (in dollars per energy unit) | $ / MWh | 230.37
Customer migration rate (percent) | 20.00%
Interest Rate Swap [Member] | NextEra Energy Resources [Member] |
Fair Value Inputs, Assets, Quantitative Information [Line Items] |
Liabilities, Fair Value Disclosure | $ 117
Derivative Financial Instruments, Liabilities [Member] |
Fair Value Inputs, Assets, Quantitative Information [Line Items] |
Liabilities, Fair Value Disclosure | 484
Derivative Financial Instruments, Liabilities [Member] | Forward Contracts - Power [Member] | Discounted Cash Flow Member] |
Fair Value Inputs, Assets, Quantitative Information [Line Items] |
Liabilities, Fair Value Disclosure | 216
Derivative Financial Instruments, Liabilities [Member] | Forward contracts - Gas [Member] | Discounted Cash Flow Member] |
Fair Value Inputs, Assets, Quantitative Information [Line Items] |
Liabilities, Fair Value Disclosure | 11
Derivative Financial Instruments, Liabilities [Member] | Option Contracts, Power [Member] | Option Models [Member] |
Fair Value Inputs, Assets, Quantitative Information [Line Items] |
Liabilities, Fair Value Disclosure | 22
Derivative Financial Instruments, Liabilities [Member] | Option Contracts, Primarily Gas [Member] | Option Models [Member] |
Fair Value Inputs, Assets, Quantitative Information [Line Items] |
Liabilities, Fair Value Disclosure | 208
Derivative Financial Instruments, Liabilities [Member] | Full Requirements and Unit Contingent Contracts [Member] | Discounted Cash Flow Member] |
Fair Value Inputs, Assets, Quantitative Information [Line Items] |
Liabilities, Fair Value Disclosure | 27
Derivative Financial Instruments, Assets [Member] |
Fair Value Inputs, Assets, Quantitative Information [Line Items] |
Assets, Fair Value Disclosure | 1,325
Derivative Financial Instruments, Assets [Member] | Forward Contracts - Power [Member] | Discounted Cash Flow Member] |
Fair Value Inputs, Assets, Quantitative Information [Line Items] |
Assets, Fair Value Disclosure | 762
Derivative Financial Instruments, Assets [Member] | Forward contracts - Gas [Member] | Discounted Cash Flow Member] |
Fair Value Inputs, Assets, Quantitative Information [Line Items] |
Assets, Fair Value Disclosure | 24
Derivative Financial Instruments, Assets [Member] | Option Contracts, Power [Member] | Option Models [Member] |
Fair Value Inputs, Assets, Quantitative Information [Line Items] |
Assets, Fair Value Disclosure | 33
Derivative Financial Instruments, Assets [Member] | Option Contracts, Primarily Gas [Member] | Option Models [Member] |
Fair Value Inputs, Assets, Quantitative Information [Line Items] |
Assets, Fair Value Disclosure | 187
Derivative Financial Instruments, Assets [Member] | Full Requirements and Unit Contingent Contracts [Member] | Discounted Cash Flow Member] |
Fair Value Inputs, Assets, Quantitative Information [Line Items] |
Assets, Fair Value Disclosure | $ 319

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- Definition Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258 + Details
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