Commitments and Contingencies (Nuclear Operations) (Narrative) (Detail) - Kewaunee $ in Millions	Mar. 31, 2018 USD ($)
Loss Contingencies [Line Items]
Liability coverage	$ 100
Property insurance limit	$ 50

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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