Risk Management and Hedging Activities - PacifiCorp - Not Designated as Hedging Contracts (Details) - Not Designated as Hedging Instrument [Member] - Commodity derivative [Member] - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Regulatory Assets (Liabilities), Net, Unrealized Loss (Gain), Net, on Derivative Instruments [Line Items]
Beginning balance	$ 253	$ 255	$ 250	$ 223
Changes in fair value recognized in net regulatory assets	(49)	(3)	(13)	57
Net (losses) gains reclassified to operating revenue	(3)	(2)	(3)	7
Ending balance	185	233	185	233
PacifiCorp [Member]
Regulatory Assets (Liabilities), Net, Unrealized Loss (Gain), Net, on Derivative Instruments [Line Items]
Beginning balance	144	130	133	85
Changes in fair value recognized in net regulatory assets	(45)	(21)	(19)	27
Net (losses) gains reclassified to operating revenue	2	3	10	28
Net Gains (Losses) Reclassified To Cost Of Domestic Regulated Electric	(12)	(13)	(35)	(41)
Ending balance	$ 89	$ 99	$ 89	$ 99