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Goodwill and Other Intangibles - Out of Market Contracts (Details) - Out of Market Contracts $ in Millions | 12 Months Ended
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Dec. 31, 2017 USD ($)
Out of Market Contracts Five Year Maturity |
2018 | $ 25
2019 | 25
2020 | 26
2021 | 23
2022 | 10
Power Contracts |
Out of Market Contracts Five Year Maturity |
2018 | 16
2019 | 16
2020 | 17
2021 | 14
2022 | 1
Lease Agreements |
Out of Market Contracts Five Year Maturity |
2018 | 9
2019 | 9
2020 | 9
2021 | 9
2022 | $ 9

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- Definition The amount of amortization for out-of-market contracts expected to be recognized during the fourth twelve-month period following the balance sheet date. + References No definition available. + Details
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- Definition The amount of amortization for out-of-market contracts expected to be recognized during the twelve-month period following the balance sheet date. + References No definition available. + Details
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