Asset Retirement Obligations - PacifiCorp - Asset Retirement Obligations By Type (Details) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
Asset Retirement Obligations By Type [Line Items]
Regulatory liabilities	$ 7,309	$ 2,933
PacifiCorp [Member]
Asset Retirement Obligations By Type [Line Items]
Regulatory liabilities	2,996	978
PacifiCorp [Member] \| Removal Costs [Member]
Asset Retirement Obligations By Type [Line Items]
Regulatory liabilities	$ 955	$ 917

The amount for the individual regulatory noncurrent liability as itemized in a table of regulatory noncurrent liabilities as of the end of the period.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.24)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Name:	us-gaap_RegulatoryLiabilityNoncurrent
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant