Risk Management and Hedging Activities - PacifiCorp - Balance Sheet Location (Details) - USD ($) $ in Millions	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015
Derivatives, Fair Value [Line Items]
Derivative, fair value, net	$ (100)		$ (77)
Cash collateral, net receivable, offset against derivative positions	84		74
Derivative assets (liabilities), at fair value, net	(16)		(3)
Other Current Assets [Member]
Derivatives, Fair Value [Line Items]
Derivative, fair value, net	30		48
Cash collateral, net receivable, offset against derivative positions	0		0
Derivative assets (liabilities), at fair value, net	30		48
Other Assets [Member]
Derivatives, Fair Value [Line Items]
Derivative, fair value, net	93		94
Cash collateral, net receivable, offset against derivative positions	0		0
Derivative assets (liabilities), at fair value, net	93		94
Other Current Liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative, fair value, net	(67)		(60)
Cash collateral, net receivable, offset against derivative positions	20		13
Derivative assets (liabilities), at fair value, net	(47)		(47)
Other Noncurrent Liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative, fair value, net	(156)		(159)
Cash collateral, net receivable, offset against derivative positions	64		61
Derivative assets (liabilities), at fair value, net	(92)		(98)
Not Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative, fair value, net	(82)		(66)
Not Designated as Hedging Instrument [Member] | Other Current Assets [Member]
Derivatives, Fair Value [Line Items]
Derivative, fair value, net	30		47
Not Designated as Hedging Instrument [Member] | Other Assets [Member]
Derivatives, Fair Value [Line Items]
Derivative, fair value, net	87		86
Not Designated as Hedging Instrument [Member] | Other Current Liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative, fair value, net	(54)		(45)
Not Designated as Hedging Instrument [Member] | Other Noncurrent Liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative, fair value, net	(145)		(154)
Commodity derivative [Member] | Not Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative asset, fair value, gross asset including not subject to master netting arrangement	116		135
Derivative Liability, Fair Value, Gross Liability Including Not Subject to Master Netting Arrangement	(199)		(206)
Derivative, fair value, net	(83)		(71)
Net Regulatory Asset (Liability), Unrealized Loss (Gain) On Derivative Contracts	162	$ 180	148	$ 185	$ 253	$ 250
Commodity derivative [Member] | Not Designated as Hedging Instrument [Member] | Other Current Assets [Member]
Derivatives, Fair Value [Line Items]
Derivative asset, fair value, gross asset including not subject to master netting arrangement	22		42
Derivative Liability, Fair Value, Gross Liability Including Not Subject to Master Netting Arrangement	(4)		(10)
Commodity derivative [Member] | Not Designated as Hedging Instrument [Member] | Other Assets [Member]
Derivatives, Fair Value [Line Items]
Derivative asset, fair value, gross asset including not subject to master netting arrangement	88		86
Derivative Liability, Fair Value, Gross Liability Including Not Subject to Master Netting Arrangement	(1)		0
Commodity derivative [Member] | Not Designated as Hedging Instrument [Member] | Other Current Liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative asset, fair value, gross asset including not subject to master netting arrangement	5		5
Derivative Liability, Fair Value, Gross Liability Including Not Subject to Master Netting Arrangement	(55)		(46)
Commodity derivative [Member] | Not Designated as Hedging Instrument [Member] | Other Noncurrent Liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative asset, fair value, gross asset including not subject to master netting arrangement	1		2
Derivative Liability, Fair Value, Gross Liability Including Not Subject to Master Netting Arrangement	(139)		(150)
PacifiCorp [Member] | Commodity derivative [Member]
Derivatives, Fair Value [Line Items]
Derivative, fair value, net	(99)		(77)
Cash collateral, net receivable, offset against derivative positions	73		69
Derivative assets (liabilities), at fair value, net	(26)		(8)
PacifiCorp [Member] | Commodity derivative [Member] | Other Current Assets [Member]
Derivatives, Fair Value [Line Items]
Derivative, fair value, net	6		18
Cash collateral, net receivable, offset against derivative positions	0		0
Derivative assets (liabilities), at fair value, net	6		18
PacifiCorp [Member] | Commodity derivative [Member] | Other Assets [Member]
Derivatives, Fair Value [Line Items]
Derivative, fair value, net	0		2
Cash collateral, net receivable, offset against derivative positions	0		0
Derivative assets (liabilities), at fair value, net	0		2
PacifiCorp [Member] | Commodity derivative [Member] | Other Current Liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative, fair value, net	(21)		(13)
Cash collateral, net receivable, offset against derivative positions	15		10
Derivative assets (liabilities), at fair value, net	(6)		(3)
PacifiCorp [Member] | Commodity derivative [Member] | Other Noncurrent Liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative, fair value, net	(84)		(84)
Cash collateral, net receivable, offset against derivative positions	58		59
Derivative assets (liabilities), at fair value, net	(26)		(25)
PacifiCorp [Member] | Commodity derivative [Member] | Not Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative asset, fair value, gross asset including not subject to master netting arrangement	10		27
Derivative Liability, Fair Value, Gross Liability Including Not Subject to Master Netting Arrangement	(109)		(104)
Derivative, fair value, net	(99)		(77)
Net Regulatory Asset (Liability), Unrealized Loss (Gain) On Derivative Contracts	95	$ 103	73	$ 89	$ 144	$ 133
PacifiCorp [Member] | Commodity derivative [Member] | Not Designated as Hedging Instrument [Member] | Other Current Assets [Member]
Derivatives, Fair Value [Line Items]
Derivative asset, fair value, gross asset including not subject to master netting arrangement	9		24
Derivative Liability, Fair Value, Gross Liability Including Not Subject to Master Netting Arrangement	(3)		(6)
Derivative, fair value, net	6		18
PacifiCorp [Member] | Commodity derivative [Member] | Not Designated as Hedging Instrument [Member] | Other Assets [Member]
Derivatives, Fair Value [Line Items]
Derivative asset, fair value, gross asset including not subject to master netting arrangement	0		2
Derivative Liability, Fair Value, Gross Liability Including Not Subject to Master Netting Arrangement	0		0
Derivative, fair value, net	0		2
PacifiCorp [Member] | Commodity derivative [Member] | Not Designated as Hedging Instrument [Member] | Other Current Liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative asset, fair value, gross asset including not subject to master netting arrangement	1		1
Derivative Liability, Fair Value, Gross Liability Including Not Subject to Master Netting Arrangement	(22)		(14)
Derivative, fair value, net	(21)		(13)
PacifiCorp [Member] | Commodity derivative [Member] | Not Designated as Hedging Instrument [Member] | Other Noncurrent Liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative asset, fair value, gross asset including not subject to master netting arrangement	0		0
Derivative Liability, Fair Value, Gross Liability Including Not Subject to Master Netting Arrangement	(84)		(84)
Derivative, fair value, net	$ (84)		$ (84)