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Condensed Statements of Comprehensive Income - MPC (Parenthetical) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2025 | Sep. 30, 2024 | Sep. 30, 2025 | Sep. 30, 2024
Changes in fair value, tax | $ (5) | $ (1) | $ 12 | $ (2)
Mississippi Power |  |  |  |
Changes in fair value, tax | $ 0 | $ 0 | $ 0 | $ 2

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- Definition Amount, before reclassification, of tax expense (benefit) for gain (loss) from derivative instrument designated and qualifying as cash flow hedge included in assessment of hedge effectiveness. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 220 -SubTopic 10 -Name Accounting Standards Codification -Section 45 -Paragraph 12 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482790/220-10-45-12 + Details
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- Details
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