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Renewable Energy Production Tax Credits recognized during the period.

No definition available.

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Related party transaction, cash received (paid) for income taxes, net

No definition available.

Name:	bhe_RelatedPartyTransactionCashPaidReceivedForIncomeTaxesNet
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The number of years from its in-service date that each wind-powered generating facility is eligible for federal renewable energy production tax credits.

No definition available.

Name:	bhe_YearsEligibleForRenewableEnergyProductionTaxCredit
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- References

No definition available.

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Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 12
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- References

No definition available.

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Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section S99
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-Section 50
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Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to other adjustments.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32687-109319

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
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-Name Accounting Standards Codification
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-Section S99
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-Subparagraph (SAB Topic 6.I.Fact.4)
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-Name Accounting Standards Codification
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-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 6.I.Fact.4)
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-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
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Name:	us-gaap_EffectiveIncomeTaxRateReconciliationStateAndLocalIncomeTaxes
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Name:	us-gaap_EffectiveIncomeTaxRateReconciliationTaxCredits
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- References

No definition available.