Recent Financing Transactions Recent Financing Transactions - NPC (Details) - Nevada Power Company [Member] $ in Millions	Jan. 31, 2017 USD ($)
Pollution Control Revenue Bonds, Variable-Rate, Series 2006 due 2036 [Member]
Debt Instrument [Line Items]
Debt Instrument, Repurchase Amount	$ 38
Pollution Control Revenue Bonds, Variable-Rate, Series 2006A due 2036 [Member]
Debt Instrument [Line Items]
Debt Instrument, Repurchase Amount	$ 38

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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