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INCOME TAX EXPENSE - Reconciliation of Taxes from Federal Statutory Rate to Total Income Tax Expense (Details) - USD ($) $ in Millions | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2025 | Jun. 30, 2024 | Jun. 30, 2025 | Jun. 30, 2024
Reconciliation of Taxes from Federal Statutory Rate to Total Income Tax Expense [Abstract] |  |  |  |
Income Before Income Taxes | $ 6.0 | $ 21.1 | $ 48.2 | $ 62.1
Statutory Federal Income Tax Rate | 21.00% | 21.00% | 21.00% | 21.00%
Income Taxes Computed at Statutory Federal Rate | $ 1.2 | $ 4.4 | $ 10.1 | $ 13.0
Increase (Decrease) in Income Tax Due to: |  |  |  |
State Income Taxes – Net of Federal Income Tax Benefit | 0.9 | 2.5 | 5.7 | 7.1
Production Tax Credits | (1.6) | (5.1) | (6.4) | (16.7)
Investment Tax Credits | (0.8) | (0.9) | (3.6) | (1.2)
Regulatory Differences – Excess Deferred Tax | (1.9) | (2.2) | (4.5) | (5.7)
Non-Controlling Interest in Subsidiaries | 4.9 | 2.4 | 8.9 | 5.2
AFUDC – Equity | (0.3) | (0.3) | (0.7) | (0.9)
Nondeductible Portion of Transaction Costs | 0.5 | 3.3 | 0.8 | 3.3
Other | (3.5) | (2.7) | (3.4) | 1.3
Total Income Tax Expense (Benefit) | $ (0.6) | $ 1.4 | $ 6.9 | $ 5.4

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