Income Taxes - PacifiCorp - Component of Net Deferred Income Tax Liability (Details) - USD ($) $ in Millions	Dec. 31, 2016	Dec. 31, 2015
Deferred Tax Assets and Liabilities [Line Items]
Regulatory liabilities	$ 909	$ 834
AROs	326	317
Other	707	815
Total deferred income tax assets, net	3,103	3,069
Property-related items	(14,237)	(13,157)
Regulatory assets	(1,449)	(1,446)
Other	(334)	(299)
Total deferred income tax liabilities	(16,982)	(15,754)
Net deferred income tax liability	(13,879)	(12,685)
PacifiCorp [Member]
Deferred Tax Assets and Liabilities [Line Items]
Regulatory liabilities	393	374
Deferred Tax Assets, Tax Deferred Expense, Compensation and Benefits	202	189
Deferred Tax Assets, Derivative Instruments And Unamortized Contract Values	67	94
Deferred Tax Assets, Operating Loss and Tax Credit Carryforwards, State and Local	69	68
Deferred Tax Assets, Tax Deferred Expense, Reserves and Accruals, Contingencies	12	67
AROs	78	81
Other	82	88
Total deferred income tax assets, net	903	961
Property-related items	(5,161)	(5,030)
Regulatory assets	(586)	(639)
Other	(36)	(42)
Total deferred income tax liabilities	(5,783)	(5,711)
Net deferred income tax liability	$ (4,880)	$ (4,750)