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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 | 9 Months Ended
--- | --- | ---
Sep. 30, 2024 | Sep. 30, 2023 | Sep. 30, 2024 | Sep. 30, 2023
Reconciliation of Taxes from Federal Statutory Rate to Total Income Tax Expense [Abstract] |  |  |  |
Income Before Income Taxes | $ 35.6 | $ 88.9 | $ 97.7 | $ 168.3
Statutory Federal Income Tax Rate | 21.00% | 21.00% | 21.00% | 21.00%
Income Taxes Computed at Statutory Federal Rate | $ 7.5 | $ 18.7 | $ 20.5 | $ 35.3
Increase (Decrease) in Income Tax Due to: |  |  |  |
State Income Taxes – Net of Federal Income Tax Benefit | 3.4 | 8.0 | 10.5 | 15.0
Production Tax Credits | (8.3) | (7.7) | (25.0) | (28.3)
Investment Tax Credits | (0.4) | (1.6) | (1.6) | (5.2)
Regulatory Differences – Excess Deferred Tax | (2.0) | (2.3) | (7.7) | (7.5)
Non-Controlling Interest in Subsidiaries | 2.4 | 3.0 | 7.6 | 8.9
AFUDC – Equity | (0.4) | 0.0 | (1.3) | 0.0
Nondeductible Portion of Transaction Costs | 0.7 | 0.0 | 4.0 | 0.0
Other | 0.0 | 1.2 | 1.3 | 2.2
Total Income Tax Expense | $ 2.9 | $ 19.3 | $ 8.3 | $ 20.4

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