Commitments And Contingencies (Nuclear Insurance) (Details) $ in Millions	3 Months Ended
Sep. 30, 2017 USD ($)
Long-term Purchase Commitment [Line Items]
Maximum Aggregate Annual Retrospective Premium Obligation	$ 58
EMANI Policy Limit	$ 200

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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