Revenue from Contract with Customer Revenue from Contract with Customer - SPPC (Details) - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax		$ 14,972
Revenues		19,787	$ 18,614	$ 17,422
Non-contracts with customer revenue [Member]
Disaggregation of Revenue [Line Items]
Revenues	[1]	601
Regulated Operation [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax		13,612
Regulated Operation [Member] | Regulated retail electric [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax		9,419
Regulated Operation [Member] | Regulated retail gas [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax		737
Sierra Pacific Power Company [Member]
Disaggregation of Revenue [Line Items]
Revenues		855	$ 812	$ 812
Sierra Pacific Power Company [Member] | Non-contracts with customer revenue [Member]
Disaggregation of Revenue [Line Items]
Revenues		6
Sierra Pacific Power Company [Member] | Electric Operations [Member]
Disaggregation of Revenue [Line Items]
Revenues		752
Sierra Pacific Power Company [Member] | Electric Operations [Member] | Non-contracts with customer revenue [Member]
Disaggregation of Revenue [Line Items]
Revenues		4
Sierra Pacific Power Company [Member] | Regulated Gas [Member]
Disaggregation of Revenue [Line Items]
Revenues		103
Sierra Pacific Power Company [Member] | Regulated Gas [Member] | Non-contracts with customer revenue [Member]
Disaggregation of Revenue [Line Items]
Revenues		2
Sierra Pacific Power Company [Member] | Regulated Operation [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax		849
Sierra Pacific Power Company [Member] | Regulated Operation [Member] | Regulated wholesale, transmission and other [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax		48
Sierra Pacific Power Company [Member] | Regulated Operation [Member] | Electric Operations [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax		748
Sierra Pacific Power Company [Member] | Regulated Operation [Member] | Electric Operations [Member] | Regulated wholesale, transmission and other [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax		48
Sierra Pacific Power Company [Member] | Regulated Operation [Member] | Regulated Gas [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax		101
Sierra Pacific Power Company [Member] | Regulated Operation [Member] | Regulated Gas [Member] | Regulated wholesale, transmission and other [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax		$ 0

[1] (2)Includes net payments to counterparties for the financial settlement of certain derivative contracts at BHE Pipeline Group.