Jointly Owned Utility Facilities - NPC (Details) $ in Millions	12 Months Ended
Dec. 31, 2017 USD ($)
Jointly Owned Utility Plant Interests [Line Items]
Jointly Owned Utility Plant, Gross Ownership Amount of Plant in Service	$ 9,651
Jointly Owned Utility Plant, Ownership Amount of Plant Accumulated Depreciation	4,353
Jointly Owned Utility Plant, Ownership Amount of Construction Work in Progress	183
Nevada Power Company [Member]
Jointly Owned Utility Plant Interests [Line Items]
Jointly Owned Utility Plant, Gross Ownership Amount of Plant in Service	414
Jointly Owned Utility Plant, Ownership Amount of Plant Accumulated Depreciation	194
Jointly Owned Utility Plant, Ownership Amount of Construction Work in Progress	$ 0
Nevada Power Company [Member] \| Navajo Generating Station [Member]
Jointly Owned Utility Plant Interests [Line Items]
Jointly Owned Utility Plant, Proportionate Ownership Share	11.00%
Jointly Owned Utility Plant, Gross Ownership Amount of Plant in Service	$ 220
Jointly Owned Utility Plant, Ownership Amount of Plant Accumulated Depreciation	152
Jointly Owned Utility Plant, Ownership Amount of Construction Work in Progress	$ 0
Nevada Power Company [Member] \| ON Line Transmission Line [Member]
Jointly Owned Utility Plant Interests [Line Items]
Jointly Owned Utility Plant, Proportionate Ownership Share	24.00%
Jointly Owned Utility Plant, Gross Ownership Amount of Plant in Service	$ 146
Jointly Owned Utility Plant, Ownership Amount of Plant Accumulated Depreciation	16
Jointly Owned Utility Plant, Ownership Amount of Construction Work in Progress	$ 0
Nevada Power Company [Member] \| Other Transmission Facilities [Member]
Jointly Owned Utility Plant Interests [Line Items]
Jointly Owned Utility Plant, Proportionate Ownership Percentage Share	Various
Jointly Owned Utility Plant, Gross Ownership Amount of Plant in Service	$ 48
Jointly Owned Utility Plant, Ownership Amount of Plant Accumulated Depreciation	26
Jointly Owned Utility Plant, Ownership Amount of Construction Work in Progress	$ 0

The proportionate share of interest (percent) in a jointly owned utility plant.

No definition available.

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Namespace Prefix:	bhe_
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- Definition

The period end amount owned by the reporting utility of a jointly owned utility plant in service.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 980
-SubTopic 360
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 10.C)
-URI http://asc.fasb.org/extlink&oid=6500719&loc=d3e659983-123033

+ Details

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Balance Type:	debit
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- Definition

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.

+ References

No definition available.

+ Details

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- Definition

The period end amount of construction work in progress at a jointly owned electricity generation plant.

+ References

+ Details

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- Definition

The period end amount of accumulated depreciation in a jointly owned electricity generation plant.

+ References

+ Details

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- Definition

The proportionate share of interest (percent) in a jointly owned utility plant.

+ References

+ Details

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- Details

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- Details

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- Details

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- Details

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