Risk Management and Hedging Activities - PacifiCorp - Not Designated as Hedging Contracts (Details) - Not Designated as Hedging Instrument [Member] - Commodity Contract [Member] - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Regulatory Assets (Liabilities), Net, Derivatives [Roll Forward]
Beginning balance	$ 223	$ 182	$ 235
Changes In Fair Value Derivatives Recognized In Regulatory Assets Or Liabilities, Net	128	96	29
Net Gains (Losses) Reclassified To Operating Revenue	1	(32)	8
Ending balance	250	223	182
PacifiCorp [Member]
Regulatory Assets (Liabilities), Net, Derivatives [Roll Forward]
Beginning balance	85	55
Changes In Fair Value Derivatives Recognized In Regulatory Assets Or Liabilities, Net	82	45
Net Gains (Losses) Reclassified To Operating Revenue	40	(4)
Net Gains (Losses) Reclassified To Cost Of Domestic Regulated Electric	(74)	(11)
Ending balance	$ 133	$ 85	$ 55