XML 168 R161.htm IDEA: XBRL DOCUMENT
v3.6.0.2

Fair Value Measurements and Financial Instruments - Volume of Derivative Activity (Details) - Not designated as hedging instrument kJ in Trillions | 12 Months Ended
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Dec. 31, 2016 GWh kJ contract
Electricity swap contracts |
Derivative Instruments and Hedging Activities Disclosures [Line Items] |
Number of contracts | contract | 8
Electricity swap contracts, 2017 |
Derivative Instruments and Hedging Activities Disclosures [Line Items] |
Volume (gwh / kj) | GWh | 1,089
Electricity swap contracts, 2018 |
Derivative Instruments and Hedging Activities Disclosures [Line Items] |
Volume (gwh / kj) | GWh | 657
Electricity swap contracts, 2019 |
Derivative Instruments and Hedging Activities Disclosures [Line Items] |
Volume (gwh / kj) | GWh | 438
Electricity swap contracts, 2020 |
Derivative Instruments and Hedging Activities Disclosures [Line Items] |
Volume (gwh / kj) | GWh | 0
Electricity swap contracts, 2021 |
Derivative Instruments and Hedging Activities Disclosures [Line Items] |
Volume (gwh / kj) | GWh | 0
Electricity swap contracts thereafter |
Derivative Instruments and Hedging Activities Disclosures [Line Items] |
Volume (gwh / kj) | GWh | 0
Electricity power purchase contracts |
Derivative Instruments and Hedging Activities Disclosures [Line Items] |
Number of contracts | contract | 39
Electricity power purchase contracts, 2017 |
Derivative Instruments and Hedging Activities Disclosures [Line Items] |
Volume (gwh / kj) | GWh | 1,252
Electricity power purchase contracts, 2018 |
Derivative Instruments and Hedging Activities Disclosures [Line Items] |
Volume (gwh / kj) | GWh | 0
Electricity power purchase contracts, 2019 |
Derivative Instruments and Hedging Activities Disclosures [Line Items] |
Volume (gwh / kj) | GWh | 0
Electricity power purchase contracts, 2020 |
Derivative Instruments and Hedging Activities Disclosures [Line Items] |
Volume (gwh / kj) | GWh | 0
Electricity power purchase contracts, 2021 |
Derivative Instruments and Hedging Activities Disclosures [Line Items] |
Volume (gwh / kj) | GWh | 0
Electricity power purchase contracts, thereafter |
Derivative Instruments and Hedging Activities Disclosures [Line Items] |
Volume (gwh / kj) | GWh | 0
Gas swap and option contracts |
Derivative Instruments and Hedging Activities Disclosures [Line Items] |
Number of contracts | contract | 108
Gas swap and option contracts, 2017 |
Derivative Instruments and Hedging Activities Disclosures [Line Items] |
Volume (gwh / kj) | 20
Gas swap and option contracts, 2018 |
Derivative Instruments and Hedging Activities Disclosures [Line Items] |
Volume (gwh / kj) | 11
Gas swap and option contracts, 2019 |
Derivative Instruments and Hedging Activities Disclosures [Line Items] |
Volume (gwh / kj) | 4
Gas swap and option contracts, 2020 |
Derivative Instruments and Hedging Activities Disclosures [Line Items] |
Volume (gwh / kj) | 0
Gas swap and option contracts, 2021 |
Derivative Instruments and Hedging Activities Disclosures [Line Items] |
Volume (gwh / kj) | 0
Gas swap and option contracts, thereafter |
Derivative Instruments and Hedging Activities Disclosures [Line Items] |
Volume (gwh / kj) | 0
Gas supply contract premiums, subject to regulatory deferral |
Derivative Instruments and Hedging Activities Disclosures [Line Items] |
Number of contracts | contract | 85
Gas supply contract premiums, subject to regulatory deferral, 2017 |
Derivative Instruments and Hedging Activities Disclosures [Line Items] |
Volume (gwh / kj) | 82
Gas supply contract premiums, subject to regulatory deferral, 2018 |
Derivative Instruments and Hedging Activities Disclosures [Line Items] |
Volume (gwh / kj) | 45
Gas supply contract premiums, subject to regulatory deferral, 2019 |
Derivative Instruments and Hedging Activities Disclosures [Line Items] |
Volume (gwh / kj) | 26
Gas supply contract premiums, subject to regulatory deferral, 2020 |
Derivative Instruments and Hedging Activities Disclosures [Line Items] |
Volume (gwh / kj) | 22
Gas supply contract premiums, subject to regulatory deferral, 2021 |
Derivative Instruments and Hedging Activities Disclosures [Line Items] |
Volume (gwh / kj) | 22
Gas supply contract premiums, subject to regulatory deferral, thereafter |
Derivative Instruments and Hedging Activities Disclosures [Line Items] |
Volume (gwh / kj) | 43
Long-term wholesale trading contracts |
Derivative Instruments and Hedging Activities Disclosures [Line Items] |
Number of contracts | contract | 18
Long-term wholesale trading contracts, 2017 |
Derivative Instruments and Hedging Activities Disclosures [Line Items] |
Volume (gwh / kj) | GWh | 2,058
Long-term wholesale trading contracts, 2018 |
Derivative Instruments and Hedging Activities Disclosures [Line Items] |
Volume (gwh / kj) | GWh | 0
Long-term wholesale trading contracts, 2019 |
Derivative Instruments and Hedging Activities Disclosures [Line Items] |
Volume (gwh / kj) | GWh | 0
Long-term wholesale trading contracts, 2020 |
Derivative Instruments and Hedging Activities Disclosures [Line Items] |
Volume (gwh / kj) | GWh | 0
Long-term wholesale trading contracts, 2021 |
Derivative Instruments and Hedging Activities Disclosures [Line Items] |
Volume (gwh / kj) | GWh | 0
Long-term wholesale trading contracts, thereafter |
Derivative Instruments and Hedging Activities Disclosures [Line Items] |
Volume (gwh / kj) | GWh | 0
Gas supply contract premiums, not subject to regulatory deferral |
Derivative Instruments and Hedging Activities Disclosures [Line Items] |
Number of contracts | contract | 226
Gas supply contract premiums, not subject to regulatory deferral, 2017 |
Derivative Instruments and Hedging Activities Disclosures [Line Items] |
Volume (gwh / kj) | 15
Gas supply contract premiums, not subject to regulatory deferral, 2018 |
Derivative Instruments and Hedging Activities Disclosures [Line Items] |
Volume (gwh / kj) | 0
Gas supply contract premiums, not subject to regulatory deferral, 2019 |
Derivative Instruments and Hedging Activities Disclosures [Line Items] |
Volume (gwh / kj) | 0
Gas supply contract premiums, not subject to regulatory deferral, 2020 |
Derivative Instruments and Hedging Activities Disclosures [Line Items] |
Volume (gwh / kj) | 0
Gas supply contract premiums, not subject to regulatory deferral, 2021 |
Derivative Instruments and Hedging Activities Disclosures [Line Items] |
Volume (gwh / kj) | 0
Gas supply contract premiums, not subject to regulatory deferral, thereafter |
Derivative Instruments and Hedging Activities Disclosures [Line Items] |
Volume (gwh / kj) | 0
Gas swap contracts |
Derivative Instruments and Hedging Activities Disclosures [Line Items] |
Number of contracts | contract | 7
Gas swap contracts, not subject to regulatory deferral, 2017 |
Derivative Instruments and Hedging Activities Disclosures [Line Items] |
Volume (gwh / kj) | 4
Gas swap contracts, not subject to regulatory deferral, 2018 |
Derivative Instruments and Hedging Activities Disclosures [Line Items] |
Volume (gwh / kj) | 0
Gas swap contracts, not subject to regulatory deferral, 2019 |
Derivative Instruments and Hedging Activities Disclosures [Line Items] |
Volume (gwh / kj) | 0
Gas swap contracts, not subject to regulatory deferral, 2020 |
Derivative Instruments and Hedging Activities Disclosures [Line Items] |
Volume (gwh / kj) | 0
Gas swap contracts, not subject to regulatory deferral, 2021 |
Derivative Instruments and Hedging Activities Disclosures [Line Items] |
Volume (gwh / kj) | 0
Gas swap contracts, not subject to regulatory deferral, thereafter |
Derivative Instruments and Hedging Activities Disclosures [Line Items] |
Volume (gwh / kj) | 0

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- Definition The number of derivative instruments of a particular group held by the entity. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 1B -URI http://asc.fasb.org/extlink&oid=64837297&loc=SL5580258-113959 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 1A -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=64837297&loc=SL5579245-113959 + Details
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