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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, 2024 USD ($) MWh MMBTU | Sep. 30, 2023 USD ($) MWh MMBTU | Sep. 30, 2024 USD ($) MWh MMBTU | Sep. 30, 2023 USD ($) MWh MMBTU
Realized gains and losses |  |  |  |
Gains (losses) | $ (20.0) | $ (34.4) | $ (103.1) | $ (174.3)
Natural gas contracts |  |  |  |
Realized gains and losses |  |  |  |
Gains (losses) | $ (24.0) | $ (56.3) | $ (110.7) | $ (200.7)
Notional sales volumes |  |  |  |
Notional sales volumes | MMBTU | 38.6 | 37.8 | 154.5 | 144.2
FTRs and TCRs |  |  |  |
Realized gains and losses |  |  |  |
Gains (losses) | $ 4.0 | $ 21.9 | $ 7.6 | $ 26.4
Notional sales volumes |  |  |  |
Notional sales volumes | MWh | 7.9 | 8.1 | 23.1 | 22.9
Non-Utility Energy Infrastructure |  |  |  |
Realized gains and losses |  |  |  |
Realized gains and losses on derivatives income statement location | Total operating revenues | Total operating revenues | Total operating revenues | Total operating revenues
Utility operations |  |  |  |
Realized gains and losses |  |  |  |
Realized gains and losses on derivatives income statement location | Cost of sales | Cost of sales | Cost of sales | Cost of sales

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- Definition Indicates line item in statement of income or comprehensive income that includes gain (loss) from derivative. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 815 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 4A -Subparagraph (b)(1) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480434/815-10-50-4A + Details
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