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v3.3.1.900

Derivative and Hedging Instruments (Details-1) $ in Thousands | 12 Months Ended |
--- | --- | ---
Dec. 31, 2015 USD ($) Dth MWh MW | Dec. 31, 2014 USD ($) Dth MWh MW | Dec. 31, 2013 USD ($)
Gross Notional Volume of Open Derivatives |  |  |
Derivative, right to reclaim collateral (receivable) | $ 1,000 | $ 2,200 |
Other Current Assets [Member] |  |  |
Derivative Fair Values [Abstract] |  |  |
Derivative fair value, net | 1,208 | 1,001 | $ 411
Commodity Contracts and Financial Transimission Rights [Member] |  |  |
Derivative Fair Values [Abstract] |  |  |
Derivative fair value, net | $ (800) | $ (1,600) |
Commodity Derivative Contracts [Member] |  |  |
Gross Notional Volume of Open Derivatives |  |  |
Notional amount, energy measure (in MWh) | MWh | 355,580 | 448,000 |
Notional amount, decatherm measure (in Dth) | Dth | 5,037,500 | 4,405,000 |
Derivative Fair Values [Abstract] |  |  |
Asset Derivatives, fair value, gross basis | $ 290 | $ 223 |
Liability Derivatives, fair value, gross basis | 1,336 | 2,433 |
Commodity Derivative Contracts [Member] | Other Current Assets [Member] |  |  |
Derivative Fair Values [Abstract] |  |  |
Asset Derivatives, fair value, gross basis | 146 | 130 |
Commodity Derivative Contracts [Member] | Other Deferred Charges [Member] |  |  |
Derivative Fair Values [Abstract] |  |  |
Asset Derivatives, fair value, gross basis | 144 | 93 |
Commodity Derivative Contracts [Member] | Derivative Liability (Current) [Member] |  |  |
Derivative Fair Values [Abstract] |  |  |
Liability Derivatives, fair value, gross basis | 1,266 | 2,262 |
Commodity Derivative Contracts [Member] | Derivative Liability (Long-term) [Member] |  |  |
Derivative Fair Values [Abstract] |  |  |
Liability Derivatives, fair value, gross basis | $ 70 | $ 171 |
Energy Related Commodity Contract [Member] | Cash Flow Hedging [Member] |  |  |
Derivatives Fair Value [Line Items] |  |  |
Maximum term of derivative hedging contract | 4 years |  |
Financial Transmission Rights [Member] |  |  |
Gross Notional Volume of Open Derivatives |  |  |
Notional amount, power measure (in MW) | MW | 2,000 | 1,854 |
Derivative Fair Values [Abstract] |  |  |
Asset Derivatives, fair value, gross basis | $ 234 | $ 642 |
Financial Transmission Rights [Member] | Other Current Assets [Member] |  |  |
Derivative Fair Values [Abstract] |  |  |
Asset Derivatives, fair value, gross basis | 234 | 642 |
Financial Transmission Rights [Member] | Derivative Liability (Current) [Member] |  |  |
Derivative Fair Values [Abstract] |  |  |
Liability Derivatives, fair value, gross basis | 0 | 0 |
PPA [Member] |  |  |
Derivative Fair Values [Abstract] |  |  |
Derivative fair value, net | (53,300) | (53,400) |
Liability Derivatives, fair value, gross basis | 53,270 | 53,430 |
PPA [Member] | Derivative Liability (Current) [Member] |  |  |
Derivative Fair Values [Abstract] |  |  |
Liability Derivatives, fair value, gross basis | 8,340 | 6,870 |
PPA [Member] | Derivative Liability (Long-term) [Member] |  |  |
Derivative Fair Values [Abstract] |  |  |
Liability Derivatives, fair value, gross basis | $ 44,930 | $ 46,560 |

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