Commitments And Contingencies (Nuclear Fuel Agreements) (Details) - Nuclear Fuel [Member] - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Long-term Purchase Commitment [Line Items]
Long Term Contract For Purchase Commitments Expiration Beginning Date	2017
Long Term Contract For Purchase Commitments Expiration Ending Date	2025
Payments for Nuclear Fuel	$ 100	$ 128	$ 105

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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