Fair Value Measurements Fair Value Measurements - SPPC - Level 3 (Details) - Sierra Pacific Power Company [Member] - Commodity [Member] - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2018	Mar. 31, 2017
Fair Value, Assets (Liabilities), Net, Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Beginning balance	$ 0	$ 0
Fair Value, Measurements with Unobservable Inputs Reconciliation, Recurring Basis, Gain (Loss) Included In Regulatory Assets and Liabilities, Net	2	0
Ending balance	$ (2)	$ 0

Amount of gain (loss) recognized in regulatory assets or liabilities, net, arising from assets, liabilities and financial instruments classified in shareholders' equity measured at fair value on a recurring basis using unobservable inputs (level 3).

No definition available.

Name:	bhe_FairValueMeasurementsWithUnobservableInputsReconciliationRecurringBasisGainLossIncludedInRegulatoryAssetsAndLiabilitiesNet
Namespace Prefix:	bhe_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration