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Income Taxes (Schedule Of Principal Components Of Net Deferred Tax Liability) (Details) - USD ($) $ in Millions | Dec. 31, 2018 | Dec. 31, 2017
--- | --- | ---
Deferred Tax Liabilities |  |
Accelerated depreciation and other property differences | $ 2,458.0 | $ 2,260.7
Other regulatory assets | 375.4 | 309.5
Total Deferred Tax Liabilities | 2,833.4 | 2,570.2
Deferred Tax Assets |  |
Deferred investment tax credits and other regulatory liabilities | 365.5 | 406.0
Pension and other postretirement/postemployment benefits | 157.5 | 136.7
Net operating loss carryforward | 849.8 | 576.0
Environmental liabilities | 24.4 | 24.0
Other accrued liabilities | 37.5 | 37.2
Other, net | 68.2 | 97.4
Total Deferred Tax Assets | 1,502.9 | 1,277.3
Net Deferred Tax Liabilities | $ 1,330.5 | $ 1,292.9

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