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Income Taxes (Schedule Of Principal Components Of Net Deferred Tax Liability) (Details) - USD ($) $ in Millions | Dec. 31, 2020 | Dec. 31, 2019
--- | --- | ---
Deferred Tax Liabilities |  |
Accelerated depreciation and other property differences | $ 2,339.3 | $ 2,516.9
Other regulatory assets | 331.8 | 381.5
Total Deferred Tax Liabilities | 2,671.1 | 2,898.4
Deferred Tax Assets |  |
Other regulatory liabilities and deferred investment tax credits (including TCJA) | 287.8 | 336.1
Pension and other postretirement/postemployment benefits | 118.1 | 152.1
Net operating loss carryforward and AMT credit carryforward | 602.1 | 765.9
Environmental liabilities | 22.6 | 25.4
Other accrued liabilities | 41.5 | 35.3
Other, net | 128.4 | 98.3
Total Deferred Tax Assets | 1,200.5 | 1,413.1
Net Deferred Tax Liabilities | $ 1,470.6 | $ 1,485.3

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