Risk Management and Hedging Activities - Balance Sheet Location (Details) - Commodity Contract [Member] - USD ($) $ in Millions		Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013
Derivatives, Fair Value [Line Items]
Derivative, Fair Value, Net		$ (103)		$ (85)
Cash collateral, net receivable, offset against derivative positions		58		28
Derivative Assets (Liabilities), at Fair Value, Net		(45)		(57)
Other Current Assets [Member]
Derivatives, Fair Value [Line Items]
Derivative, Fair Value, Net		14		18
Cash collateral, net receivable, offset against derivative positions		0		0
Derivative Assets (Liabilities), at Fair Value, Net		14		18
Other Assets [Member]
Derivatives, Fair Value [Line Items]
Derivative, Fair Value, Net		0		0
Cash collateral, net receivable, offset against derivative positions		0		0
Derivative Assets (Liabilities), at Fair Value, Net		0		0
Other Current Liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative, Fair Value, Net		(40)		(54)
Cash collateral, net receivable, offset against derivative positions		14		14
Derivative Assets (Liabilities), at Fair Value, Net		(26)		(40)
Other Long-term Liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative, Fair Value, Net		(77)		(49)
Cash collateral, net receivable, offset against derivative positions		44		14
Derivative Assets (Liabilities), at Fair Value, Net		(33)		(35)
Not Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Commodity assets	[1]	18		29
Commodity liabilities	[1]	(121)		(114)
Derivative, Fair Value, Net	[1]	(103)		(85)
Regulatory asset		99	$ 130	85	$ 0	$ 27	$ 55
Not Designated as Hedging Instrument [Member] | Other Current Assets [Member]
Derivatives, Fair Value [Line Items]
Commodity assets	[1]	17		28
Commodity liabilities	[1]	(3)		(10)
Derivative, Fair Value, Net	[1]	14		18
Not Designated as Hedging Instrument [Member] | Other Assets [Member]
Derivatives, Fair Value [Line Items]
Commodity assets	[1]	0		0
Commodity liabilities	[1]	0		0
Derivative, Fair Value, Net	[1]	0		0
Not Designated as Hedging Instrument [Member] | Other Current Liabilities [Member]
Derivatives, Fair Value [Line Items]
Commodity assets	[1]	1		1
Commodity liabilities	[1]	(41)		(55)
Derivative, Fair Value, Net	[1]	(40)		(54)
Not Designated as Hedging Instrument [Member] | Other Long-term Liabilities [Member]
Derivatives, Fair Value [Line Items]
Commodity assets	[1]	0		0
Commodity liabilities	[1]	(77)		(49)
Derivative, Fair Value, Net	[1]	$ (77)		$ (49)

[1] PacifiCorp's commodity derivatives are generally included in rates and as of June 30, 2015 and December 31, 2014, a regulatory asset of $99 million and $85 million, respectively, was recorded related to the net derivative liability of $103 million and $85 million, respectively.