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v3.25.3

FAIR VALUE MEASUREMENTS - Changes in Fair Value (Details) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2025 | Sep. 30, 2024 | Sep. 30, 2025 | Sep. 30, 2024
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward] |  |  |  |
Beginning Balance | $ 382.8 | $ 288.2 | $ 165.6 | $ 139.4
Realized Gain (Loss) Included in Net Income (or Changes in Net Assets) | 44.7 | 60.4 | 155.3 | 90.6
Unrealized Gain (Loss) Included in Net Income (or Changes in Net Assets) Relating to Assets Still Held at the Reporting Date | 13.2 | (6.9) | 31.1 | 2.3
Realized and Unrealized Gains (Losses) Included in Other Comprehensive Income | 1.5 | (0.1) | 14.0 | 1.5
Settlements | (131.6) | (133.1) | (276.9) | (164.7)
Transfers into Level 3 | 7.1 | (0.3) | 1.0 | 6.8
Transfers out of Level 3 | (5.2) | (0.6) | (3.0) | 2.2
Changes in Fair Value Allocated to Regulated Jurisdiction | 14.6 | (14.5) | 240.0 | 115.0
Ending Balance | 327.1 | 193.1 | 327.1 | 193.1
APCo |  |  |  |
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward] |  |  |  |
Beginning Balance | 108.3 | 67.8 | 35.2 | 22.4
Realized Gain (Loss) Included in Net Income (or Changes in Net Assets) | 15.6 | 13.4 | 49.4 | 24.1
Unrealized Gain (Loss) Included in Net Income (or Changes in Net Assets) Relating to Assets Still Held at the Reporting Date | 0.0 | 0.0 | 0.0 | 0.0
Realized and Unrealized Gains (Losses) Included in Other Comprehensive Income | 0.0 | 0.0 | 0.0 | 0.0
Settlements | (34.4) | (26.9) | (84.6) | (46.5)
Transfers into Level 3 | 0.0 | 0.0 | 0.0 | 0.0
Transfers out of Level 3 | 0.0 | 0.0 | 0.0 | 0.0
Changes in Fair Value Allocated to Regulated Jurisdiction | 1.8 | (7.1) | 91.3 | 47.2
Ending Balance | 91.3 | 47.2 | 91.3 | 47.2
I&M |  |  |  |
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward] |  |  |  |
Beginning Balance | 12.3 | 14.5 | 6.4 | 2.8
Realized Gain (Loss) Included in Net Income (or Changes in Net Assets) | 3.6 | 2.9 | 12.9 | 7.3
Unrealized Gain (Loss) Included in Net Income (or Changes in Net Assets) Relating to Assets Still Held at the Reporting Date | 0.0 | 0.0 | 0.0 | 0.0
Realized and Unrealized Gains (Losses) Included in Other Comprehensive Income | 0.0 | 0.0 | 0.0 | 0.0
Settlements | (7.1) | (7.9) | (19.2) | (10.0)
Transfers into Level 3 | 0.0 | 0.0 | 0.0 | 0.0
Transfers out of Level 3 | 0.0 | 0.0 | 0.0 | 0.0
Changes in Fair Value Allocated to Regulated Jurisdiction | 2.1 | (0.2) | 10.8 | 9.2
Ending Balance | 10.9 | 9.3 | 10.9 | 9.3
OPCo |  |  |  |
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward] |  |  |  |
Beginning Balance | (47.7) | (43.2) | (47.5) | (50.6)
Realized Gain (Loss) Included in Net Income (or Changes in Net Assets) | (0.1) | (0.1) | 0.0 | (0.9)
Unrealized Gain (Loss) Included in Net Income (or Changes in Net Assets) Relating to Assets Still Held at the Reporting Date | 0.0 | 0.0 | 0.0 | 0.0
Realized and Unrealized Gains (Losses) Included in Other Comprehensive Income | 0.0 | 0.0 | 0.0 | 0.0
Settlements | 1.0 | 1.0 | 5.3 | 6.0
Transfers into Level 3 | 0.0 | 0.0 | 0.0 | 0.0
Transfers out of Level 3 | 0.0 | 0.0 | 0.0 | 0.0
Changes in Fair Value Allocated to Regulated Jurisdiction | 2.5 | (9.3) | (2.1) | (6.1)
Ending Balance | (44.3) | (51.6) | (44.3) | (51.6)
PSO |  |  |  |
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward] |  |  |  |
Beginning Balance | 96.9 | 49.4 | 20.0 | 18.6
Realized Gain (Loss) Included in Net Income (or Changes in Net Assets) | 14.1 | 23.2 | 37.9 | 26.2
Unrealized Gain (Loss) Included in Net Income (or Changes in Net Assets) Relating to Assets Still Held at the Reporting Date | 0.0 | 0.0 | 0.0 | 0.0
Realized and Unrealized Gains (Losses) Included in Other Comprehensive Income | 0.0 | 0.0 | 0.0 | 0.0
Settlements | (45.2) | (46.3) | (57.9) | (44.8)
Transfers into Level 3 | 0.0 | 0.0 | 0.0 | 0.0
Transfers out of Level 3 | 0.0 | 0.0 | 0.0 | 0.0
Changes in Fair Value Allocated to Regulated Jurisdiction | (0.5) | 2.1 | 65.3 | 28.4
Ending Balance | 65.3 | 28.4 | 65.3 | 28.4
SWEPCo |  |  |  |
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward] |  |  |  |
Beginning Balance | 69.1 | 38.1 | 17.5 | 11.1
Realized Gain (Loss) Included in Net Income (or Changes in Net Assets) | 9.6 | 21.2 | 42.2 | 23.6
Unrealized Gain (Loss) Included in Net Income (or Changes in Net Assets) Relating to Assets Still Held at the Reporting Date | 0.0 | 0.0 | 0.0 | 0.0
Realized and Unrealized Gains (Losses) Included in Other Comprehensive Income | 0.0 | 0.0 | 0.0 | 0.0
Settlements | (29.9) | (37.7) | (59.7) | (36.0)
Transfers into Level 3 | 0.0 | 0.0 | 0.0 | 0.0
Transfers out of Level 3 | 0.0 | 0.0 | 0.0 | 0.5
Changes in Fair Value Allocated to Regulated Jurisdiction | 7.8 | 2.1 | 56.6 | 24.5
Ending Balance | $ 56.6 | $ 23.7 | $ 56.6 | $ 23.7

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