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v3.19.2

Derivative Accounting - Schedule of Gross Notional Amounts Outstanding (Details) - Commodity Contracts GWh in Thousands, Bcf in Thousands | Jun. 30, 2019 GWh Bcf | Dec. 31, 2018 GWh Bcf
--- | --- | ---
Outstanding gross notional amount of derivatives |  |
Power | GWh | 1,000 | 250
Gas | Bcf | 218 | 218

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