Employee Benefit Plans - PacifiCorp - Funded Status (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2015	May. 31, 2015	Dec. 31, 2014
Domestic Pension Plans [Member]
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Beginning balance	$ 2,718	$ 2,711
Defined Benefit Plan, Contributions by Employer	13	37
Defined Benefit Plan, Contributions by Plan Participants	0	0
Defined Benefit Plan, Actual Return on Plan Assets	(17)	188
Defined Benefit Plan, Settlements, Plan Assets	23	0
Defined Benefit Plan, Benefits Paid	(202)	(218)
Ending balance	2,489	2,718	$ 2,711
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]
Beginning balance	3,119	2,821
Defined Benefit Plan, Service Cost	33	36	24
Defined Benefit Plan, Interest Cost	121	131	87
Defined Benefit Plan, Contributions by Plan Participants	0	0
Defined Benefit Plan, Actuarial Gain (Loss)	(110)	349
Defined Benefit Plan, Settlements, Benefit Obligation	(23)	0
Defined Benefit Plan, Benefits Paid	(202)	(218)
Defined Benefit Plan, Benefit Obligation	3,119	2,821	2,821	$ 2,934		$ 3,119
Defined Benefit Plan, Accumulated Benefit Obligation				2,906		3,086
Defined Benefit Plan, Funded Status of Plan [Abstract]
Defined Benefit Plan, Funded Status of Plan				(445)		(401)
Other current liabilities				(15)		(14)
Pension and Other Postretirement Defined Benefit Plans, Liabilities, Noncurrent				(437)		(399)
Defined Benefit Plan, Amounts Recognized in Balance Sheet				(445)		(401)
Domestic Other Postretirement Plans [Member]
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Beginning balance	858	852
Defined Benefit Plan, Contributions by Employer	2	2
Defined Benefit Plan, Contributions by Plan Participants	9	11
Defined Benefit Plan, Actual Return on Plan Assets	0	54
Defined Benefit Plan, Settlements, Plan Assets	150	0
Defined Benefit Plan, Benefits Paid	(57)	(61)
Ending balance	662	858	852
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]
Beginning balance	936	987
Defined Benefit Plan, Service Cost	11	14	14
Defined Benefit Plan, Interest Cost	31	46	33
Defined Benefit Plan, Contributions by Plan Participants	9	11
Defined Benefit Plan, Actuarial Gain (Loss)	(43)	(61)
Defined Benefit Plan, Settlements, Benefit Obligation	(150)	0
Defined Benefit Plan, Benefits Paid	(57)	(61)
Defined Benefit Plan, Benefit Obligation	936	987	987	740		936
Defined Benefit Plan, Funded Status of Plan [Abstract]
Defined Benefit Plan, Funded Status of Plan				(78)		(78)
Other current liabilities				0		0
Pension and Other Postretirement Defined Benefit Plans, Liabilities, Noncurrent				(93)		(88)
Defined Benefit Plan, Amounts Recognized in Balance Sheet				(78)		(78)
Supplemental Employee Retirement Plan [Member]
Defined Benefit Plans, Supplemental Employee Retirement Plans [Abstract]
Life Insurance, Corporate or Bank Owned, Amount				228		247
PacifiCorp [Member] | Domestic Pension Plans [Member]
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Beginning balance	1,146	1,171
Defined Benefit Plan, Contributions by Employer	4	10
Defined Benefit Plan, Contributions by Plan Participants	0	0
Defined Benefit Plan, Actual Return on Plan Assets	0	53
Defined Benefit Plan, Settlements, Plan Assets	0	0
Defined Benefit Plan, Benefits Paid	(107)	(88)
Ending balance	1,043	1,146	1,171
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]
Beginning balance	1,378	1,230
Defined Benefit Plan, Service Cost	4	5	6
Defined Benefit Plan, Interest Cost	53	57	54
Defined Benefit Plan, Contributions by Plan Participants	0	0
Defined Benefit Plan, Actuarial Gain (Loss)	(39)	174
Defined Benefit Plan, Settlements, Benefit Obligation	0	0
Defined Benefit Plan, Benefits Paid	(107)	(88)
Defined Benefit Plan, Benefit Obligation	1,378	1,230	1,230	1,289		1,378
Defined Benefit Plan, Accumulated Benefit Obligation				1,289		1,378
Defined Benefit Plan, Funded Status of Plan [Abstract]
Defined Benefit Plan, Funded Status of Plan				(246)		(232)
Other current liabilities				(4)		(4)
Pension and Other Postretirement Defined Benefit Plans, Liabilities, Noncurrent				(242)		(228)
Defined Benefit Plan, Amounts Recognized in Balance Sheet				(246)		(232)
PacifiCorp [Member] | Domestic Other Postretirement Plans [Member]
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Beginning balance	482	486
Defined Benefit Plan, Contributions by Employer	1	1
Defined Benefit Plan, Contributions by Plan Participants	6	7
Defined Benefit Plan, Actual Return on Plan Assets	1	25
Defined Benefit Plan, Settlements, Plan Assets	150	0
Defined Benefit Plan, Benefits Paid	(35)	(37)
Ending balance	305	482	486
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]
Beginning balance	539	598
Defined Benefit Plan, Service Cost	3	6	9
Defined Benefit Plan, Interest Cost	16	28	25
Defined Benefit Plan, Contributions by Plan Participants	6	7
Defined Benefit Plan, Actuarial Gain (Loss)	(17)	(63)
Defined Benefit Plan, Settlements, Benefit Obligation	(150)	0
Defined Benefit Plan, Benefits Paid	(35)	(37)
Defined Benefit Plan, Benefit Obligation	$ 539	$ 598	$ 598	362		539
Defined Benefit Plan, Amount To Be Transferred				150	$ 150
Defined Benefit Plan, Funded Status of Plan [Abstract]
Defined Benefit Plan, Funded Status of Plan				(57)		(57)
Other current liabilities				0		0
Pension and Other Postretirement Defined Benefit Plans, Liabilities, Noncurrent				(57)		(57)
Defined Benefit Plan, Amounts Recognized in Balance Sheet				(57)		(57)
PacifiCorp [Member] | Supplemental Employee Retirement Plan [Member]
Defined Benefit Plans, Supplemental Employee Retirement Plans [Abstract]
Life Insurance, Corporate or Bank Owned, Amount				$ 52		$ 51