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Price Risk Management Future Year Net Unrealized Gain/Loss Recorded at Balance Sheet Date Expected to Become Realized (Details) $ in Millions | Jun. 30, 2017 USD ($)
--- | ---
Electricity [Member] |
Commodity contracts: |
2016 | $ 3
2017 | 6
2018 | 8
2019 | 8
2020 | 8
Thereafter | 108
Total | 141
Natural Gas [Member] |
Commodity contracts: |
2016 | 24
2017 | 20
2018 | 9
2019 | 3
2020 | 0
Thereafter | 0
Total | 56
Net Unrealized Loss [Member] |
Commodity contracts: |
2016 | 27
2017 | 26
2018 | 17
2019 | 11
2020 | 8
Thereafter | 108
Total | $ 197

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