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DERIVATIVE INSTRUMENTS - GAINS (LOSSES) AND NOTIONAL VOLUMES (Details) MWh in Millions, MMBTU in Millions, $ in Millions | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2022 USD ($) MWh MMBTU | Sep. 30, 2021 USD ($) MMBTU MWh | Sep. 30, 2022 USD ($) MMBTU MWh | Sep. 30, 2021 USD ($) MMBTU MWh
Realized gains |  |  |  |
Gains | $ 126.5 | $ 44.2 | $ 272.3 | $ 53.8
Natural gas contracts |  |  |  |
Notional sales volumes |  |  |  |
Notional sales volumes | MMBTU | 32.7 | 39.4 | 133.3 | 147.1
Realized gains |  |  |  |
Gains | $ 119.1 | $ 41.2 | $ 259.6 | $ 38.5
FTRs and TCRs |  |  |  |
Notional sales volumes |  |  |  |
Notional sales volumes | MWh | 7.0 | 6.3 | 21.0 | 22.1
Realized gains |  |  |  |
Gains | $ 7.4 | $ 3.0 | $ 12.7 | $ 15.3

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- Definition Amount of increase (decrease) in the fair value of derivatives recognized in the income statement. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4A -Subparagraph (b)(1) -URI https://asc.fasb.org/extlink&oid=125515794&loc=SL5618551-113959 + Details
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