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v3.25.3

COMPREHENSIVE INCOME (Details) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2025 | Jun. 30, 2025 | Mar. 31, 2025 | Sep. 30, 2024 | Jun. 30, 2024 | Mar. 31, 2024 | Sep. 30, 2025 | Sep. 30, 2024
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward] |  |  |  |  |  |  |  |
Beginning balance | $ 30,968.4 | $ 27,364.0 | $ 26,986.1 | $ 26,175.7 | $ 25,843.7 | $ 25,285.9 | $ 26,986.1 | $ 25,285.9
TOTAL OTHER COMPREHENSIVE INCOME (LOSS) | (15.2) | (32.9) | 23.4 | (46.9) | 22.3 | (6.8) | (24.7) | (31.4)
Ending balance | 31,479.3 | 30,968.4 | 27,364.0 | 26,658.8 | 26,175.7 | 25,843.7 | 31,479.3 | 26,658.8
Total |  |  |  |  |  |  |  |
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward] |  |  |  |  |  |  |  |
Beginning balance | (12.6) | 20.3 | (3.1) | (40.0) | (62.3) | (55.5) | (3.1) | (55.5)
Change in Fair Value Recognized in AOCI, Net of Tax | (17.2) |  |  | (53.3) |  |  | (16.0) | (21.5)
Amount of (Gain) Loss Reclassified from AOCI | 2.6 |  |  | 8.2 |  |  | (11.0) | (12.5)
Income Tax (Expense) Benefit | 0.6 |  |  | 1.8 |  |  | (2.3) | (2.6)
Reclassifications from AOCI, Net of Income Tax (Expense) Benefit | 2.0 |  |  | 6.4 |  |  | (8.7) | (9.9)
TOTAL OTHER COMPREHENSIVE INCOME (LOSS) | (15.2) | (32.9) | 23.4 | (46.9) | 22.3 | (6.8) | (24.7) | (31.4)
Ending balance | (27.8) | (12.6) | 20.3 | (86.9) | (40.0) | (62.3) | (27.8) | (86.9)
Pension and OPEB |  |  |  |  |  |  |  |
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward] |  |  |  |  |  |  |  |
Beginning balance | (104.3) |  | (104.9) | (153.0) |  | (152.3) | (104.9) | (152.3)
Change in Fair Value Recognized in AOCI, Net of Tax | 0.0 |  |  | 0.0 |  |  | 0.0 | 0.0
Amount of (Gain) Loss Reclassified from AOCI | 0.3 |  |  | (0.7) |  |  | 1.0 | (1.6)
Income Tax (Expense) Benefit | 0.1 |  |  | (0.1) |  |  | 0.2 | (0.3)
Reclassifications from AOCI, Net of Income Tax (Expense) Benefit | 0.2 |  |  | (0.6) |  |  | 0.8 | (1.3)
TOTAL OTHER COMPREHENSIVE INCOME (LOSS) | 0.2 |  |  | (0.6) |  |  | 0.8 | (1.3)
Ending balance | (104.1) | (104.3) |  | (153.6) | (153.0) |  | (104.1) | (153.6)
Amortization of Prior Service Cost (Credit) |  |  |  |  |  |  |  |
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward] |  |  |  |  |  |  |  |
Amount of (Gain) Loss Reclassified from AOCI | (0.2) |  |  | (1.4) |  |  | (0.6) | (4.0)
Amortization of Actuarial (Gains) Losses |  |  |  |  |  |  |  |
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward] |  |  |  |  |  |  |  |
Amount of (Gain) Loss Reclassified from AOCI | 0.5 |  |  | 0.7 |  |  | 1.6 | 2.4
Commodity | Cash Flow Hedges |  |  |  |  |  |  |  |
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward] |  |  |  |  |  |  |  |
Beginning balance | 91.5 |  | 98.5 | 103.7 |  | 104.9 | 98.5 | 104.9
Change in Fair Value Recognized in AOCI, Net of Tax | (17.1) |  |  | (28.8) |  |  | (14.9) | (16.3)
Amount of (Gain) Loss Reclassified from AOCI | 3.2 |  |  | 0.1 |  |  | (8.5) | (17.4)
Income Tax (Expense) Benefit | 0.7 |  |  | 0.1 |  |  | (1.8) | (3.7)
Reclassifications from AOCI, Net of Income Tax (Expense) Benefit | 2.5 |  |  | 0.0 |  |  | (6.7) | (13.7)
TOTAL OTHER COMPREHENSIVE INCOME (LOSS) | (14.6) |  |  | (28.8) |  |  | (21.6) | (30.0)
Ending balance | 76.9 | 91.5 |  | 74.9 | 103.7 |  | 76.9 | 74.9
Commodity | Cash Flow Hedges | Purchased Electricity, Fuel and Other Consumables Used for Electric Generation |  |  |  |  |  |  |  |
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward] |  |  |  |  |  |  |  |
Amount of (Gain) Loss Reclassified from AOCI | 3.2 |  |  | 0.1 |  |  | (8.5) | (17.4)
Interest Rate | Cash Flow Hedges |  |  |  |  |  |  |  |
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward] |  |  |  |  |  |  |  |
Beginning balance | 0.2 |  | $ 3.3 | 9.3 |  | $ (8.1) | 3.3 | (8.1)
Change in Fair Value Recognized in AOCI, Net of Tax | (0.1) |  |  | (24.5) |  |  | (1.1) | (5.2)
Amount of (Gain) Loss Reclassified from AOCI | (0.9) |  |  | 8.8 |  |  | (3.5) | 6.5
Income Tax (Expense) Benefit | (0.2) |  |  | 1.8 |  |  | (0.7) | 1.4
Reclassifications from AOCI, Net of Income Tax (Expense) Benefit | (0.7) |  |  | 7.0 |  |  | (2.8) | 5.1
TOTAL OTHER COMPREHENSIVE INCOME (LOSS) | (0.8) |  |  | (17.5) |  |  | (3.9) | (0.1)
Ending balance | (0.6) | $ 0.2 |  | (8.2) | $ 9.3 |  | (0.6) | (8.2)
Interest Rate | Cash Flow Hedges | Interest Expense |  |  |  |  |  |  |  |
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward] |  |  |  |  |  |  |  |
Amount of (Gain) Loss Reclassified from AOCI | $ (0.9) |  |  | $ 8.8 |  |  | $ (3.5) | $ 6.5

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