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DERIVATIVE INSTRUMENTS - GAINS (LOSSES) AND NOTIONAL VOLUMES (Details) MWh in Millions, MMBTU in Millions, $ in Millions | 3 Months Ended
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Mar. 31, 2023 USD ($) MMBTU MWh | Mar. 31, 2022 USD ($) MWh MMBTU
Realized gains and losses |  |
Gains (losses) | $ (74.9) | $ 32.6
Natural gas contracts |  |
Realized gains and losses |  |
Gains (losses) | $ (75.3) | $ 31.6
Notional sales volumes |  |
Notional sales volumes | MMBTU | 58.7 | 59.5
FTRs and TCRs |  |
Realized gains and losses |  |
Gains (losses) | $ 0.4 | $ 1.0
Notional sales volumes |  |
Notional sales volumes | MWh | 7.3 | 7.0
Non-Utility Energy Infrastructure |  |
Realized gains and losses |  |
Realized gains and losses on derivatives income statement location | 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

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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 -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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