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Income Taxes (Schedule Of Principal Components Of Net Deferred Tax Liability) (Details) - USD ($) $ in Millions | Dec. 31, 2024 | Dec. 31, 2023
--- | --- | ---
Deferred Tax Liabilities |  |
Accelerated depreciation and other property differences | $ 1,419.4 | $ 1,384.8
Partnership basis differences | 1,328.6 | 1,241.9
Other regulatory assets | 210.1 | 212.1
Total Deferred Tax Liabilities | 2,958.1 | 2,838.8
Deferred Tax Assets |  |
Other regulatory liabilities and deferred investment tax credits (including TCJA) | 170.4 | 182.2
Pension and other postretirement/postemployment benefits | 58.8 | 58.6
Net operating loss carryforward and AMT credit carryforward | 369.4 | 422.9
Environmental liabilities | 12.2 | 10.1
Other accrued liabilities | 43.4 | 40.3
Other, net | 28.7 | 50.7
Total Deferred Tax Assets | 682.9 | 764.8
Deferred Tax Assets, Valuation Allowance | (6.4) | (6.4)
Deferred Tax Assets, Net of Valuation Allowance | 676.5 | 758.4
Net Deferred Tax Liabilities | $ 2,281.6 | $ 2,080.4

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