Employee Benefit Plans - PacifiCorp - Unrecognized Amounts (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	May. 31, 2015	Dec. 31, 2013
Defined Benefit Plan, Reconciliation of Amounts Not Yet Recognized As Components of Net Periodic Benefit Cost [Roll Forward]
Defined Benefit Plan, Amortization of Gains (Losses), Net	$ 61
Defined Benefit Plan, Amortization of Prior Service Cost (Credit), Net	(27)
Defined Benefit Plan, Amortization of Regulatory Deferrals, Net	0
Defined Benefit Plan, Amounts That Will Be Amortized from Regulatory Assets (Liabilities) and Accumulated Other Comprehensive Income Loss In Next Fiscal Year	34
Domestic Pension Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Net Periodic Benefit Cost Not Yet Recognized, Net Gains (Losses), Before Tax	768	$ 757
Defined Benefit Plan, Net Periodic Benefit Cost Not Yet Recognized, Net Prior Service Cost (Credit), Before Tax	(25)	(31)
Defined Benefit Plan, Net Periodic Benefit Cost Not Yet Recognized, Regulatory Deferrals, Before Tax	(2)	(3)
Defined Benefit Plan, Net Periodic Benefit Cost Not Yet Recognized, Before Tax	741	723		$ 441
Defined Benefit Plan, Reconciliation of Amounts Not Yet Recognized As Components of Net Periodic Benefit Cost [Roll Forward]
Defined Benefit Plan, Net Unamortized Gain (Loss) Arising During Period, Before Tax	75	326
Defined Benefit Plan, Net Amortization Recognized in Net Periodic Benefit Cost Before Tax	(53)	(44)
Defined Benefit Plan, Net Periodic Benefit Cost Not Yet Recognized, Arising During Period, Before Tax	18	282
Defined Benefit Plan, Amortization of Gains (Losses), Net	58
Defined Benefit Plan, Amortization of Prior Service Cost (Credit), Net	(11)
Defined Benefit Plan, Amortization of Regulatory Deferrals, Net	(1)
Defined Benefit Plan, Amounts That Will Be Amortized from Regulatory Assets (Liabilities) and Accumulated Other Comprehensive Income Loss In Next Fiscal Year	46
Domestic Other Postretirement Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Net Periodic Benefit Cost Not Yet Recognized, Net Gains (Losses), Before Tax	97	108
Defined Benefit Plan, Net Periodic Benefit Cost Not Yet Recognized, Net Prior Service Cost (Credit), Before Tax	(68)	(87)
Defined Benefit Plan, Net Periodic Benefit Cost Not Yet Recognized, Regulatory Deferrals, Before Tax	8	2
Defined Benefit Plan, Net Periodic Benefit Cost Not Yet Recognized, Before Tax	37	23		83
Defined Benefit Plan, Reconciliation of Amounts Not Yet Recognized As Components of Net Periodic Benefit Cost [Roll Forward]
Defined Benefit Plan, Net Unamortized Gain (Loss) Arising During Period, Before Tax	0	(63)
Defined Benefit Plan, Net Amortization Recognized in Net Periodic Benefit Cost Before Tax	11	3
Defined Benefit Plan, Net Periodic Benefit Cost Not Yet Recognized, Arising During Period, Before Tax	14	(60)
Defined Benefit Plan, Amortization of Gains (Losses), Net	3
Defined Benefit Plan, Amortization of Prior Service Cost (Credit), Net	(16)
Defined Benefit Plan, Amortization of Regulatory Deferrals, Net	1
Defined Benefit Plan, Amounts That Will Be Amortized from Regulatory Assets (Liabilities) and Accumulated Other Comprehensive Income Loss In Next Fiscal Year	(12)
Regulatory Asset, Pension and Other Postretirement Costs [Member] | Domestic Pension Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Net Periodic Benefit Cost Not Yet Recognized, Before Tax	729	710		490
Defined Benefit Plan, Reconciliation of Amounts Not Yet Recognized As Components of Net Periodic Benefit Cost [Roll Forward]
Defined Benefit Plan, Net Unamortized Gain (Loss) Arising During Period, Before Tax	76	258
Defined Benefit Plan, Net Amortization Recognized in Net Periodic Benefit Cost Before Tax	(53)	(38)
Defined Benefit Plan, Net Periodic Benefit Cost Not Yet Recognized, Arising During Period, Before Tax	19	220
Defined Benefit Plan, Amortization of Prior Service Cost (Credit), Net	4
Regulatory Asset, Pension and Other Postretirement Costs [Member] | Domestic Other Postretirement Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Net Periodic Benefit Cost Not Yet Recognized, Before Tax	49	37		99
Defined Benefit Plan, Reconciliation of Amounts Not Yet Recognized As Components of Net Periodic Benefit Cost [Roll Forward]
Defined Benefit Plan, Net Unamortized Gain (Loss) Arising During Period, Before Tax	(1)	(64)
Defined Benefit Plan, Net Amortization Recognized in Net Periodic Benefit Cost Before Tax	10	2
Defined Benefit Plan, Net Periodic Benefit Cost Not Yet Recognized, Arising During Period, Before Tax	12	(62)
Defined Benefit Plan, Amortization of Prior Service Cost (Credit), Net	(3)
Accumulated Other Comprehensive Income (Loss) [Member] | Domestic Pension Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Net Periodic Benefit Cost Not Yet Recognized, Before Tax	13	19		9
Defined Benefit Plan, Reconciliation of Amounts Not Yet Recognized As Components of Net Periodic Benefit Cost [Roll Forward]
Defined Benefit Plan, Net Unamortized Gain (Loss) Arising During Period, Before Tax	(6)	16
Defined Benefit Plan, Net Amortization Recognized in Net Periodic Benefit Cost Before Tax	0	(6)
Defined Benefit Plan, Net Periodic Benefit Cost Not Yet Recognized, Arising During Period, Before Tax	(6)	10
Defined Benefit Plan, Amortization of Prior Service Cost (Credit), Net	0
PacifiCorp [Member]
Defined Benefit Plan, Reconciliation of Amounts Not Yet Recognized As Components of Net Periodic Benefit Cost [Roll Forward]
Defined Benefit Plan, Amortization of Gains (Losses), Net	43
Defined Benefit Plan, Amortization of Prior Service Cost (Credit), Net	(15)
Defined Benefit Plan, Amortization of Regulatory Deferrals, Net	0
Defined Benefit Plan, Amounts That Will Be Amortized from Regulatory Assets (Liabilities) and Accumulated Other Comprehensive Income Loss In Next Fiscal Year	28
PacifiCorp [Member] | Domestic Pension Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Net Periodic Benefit Cost Not Yet Recognized, Net Gains (Losses), Before Tax	508	520
Defined Benefit Plan, Net Periodic Benefit Cost Not Yet Recognized, Net Prior Service Cost (Credit), Before Tax	(13)	(21)
Defined Benefit Plan, Net Periodic Benefit Cost Not Yet Recognized, Regulatory Deferrals, Before Tax	(3)	(3)
Defined Benefit Plan, Net Periodic Benefit Cost Not Yet Recognized, Before Tax	492	496		328
Defined Benefit Plan, Reconciliation of Amounts Not Yet Recognized As Components of Net Periodic Benefit Cost [Roll Forward]
Defined Benefit Plan, Net Unamortized Gain (Loss) Arising During Period, Before Tax	38	197
Defined Benefit Plan, Net Amortization Recognized in Net Periodic Benefit Cost Before Tax	(42)	(29)
Defined Benefit Plan, Net Periodic Benefit Cost Not Yet Recognized, Arising During Period, Before Tax	(4)	168
Defined Benefit Plan, Amortization of Gains (Losses), Net	42
Defined Benefit Plan, Amortization of Prior Service Cost (Credit), Net	(8)
Defined Benefit Plan, Amortization of Regulatory Deferrals, Net	(1)
Defined Benefit Plan, Amounts That Will Be Amortized from Regulatory Assets (Liabilities) and Accumulated Other Comprehensive Income Loss In Next Fiscal Year	33
PacifiCorp [Member] | Domestic Other Postretirement Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Net Periodic Benefit Cost Not Yet Recognized, Net Gains (Losses), Before Tax	36	41
Defined Benefit Plan, Net Periodic Benefit Cost Not Yet Recognized, Net Prior Service Cost (Credit), Before Tax	(19)	(26)
Defined Benefit Plan, Net Periodic Benefit Cost Not Yet Recognized, Regulatory Deferrals, Before Tax	9	2	$ 9
Defined Benefit Plan, Net Periodic Benefit Cost Not Yet Recognized, Before Tax	26	17
Defined Benefit Plan, Reconciliation of Amounts Not Yet Recognized As Components of Net Periodic Benefit Cost [Roll Forward]
Defined Benefit Plan, Amortization of Gains (Losses), Net	1
Defined Benefit Plan, Amortization of Prior Service Cost (Credit), Net	(7)
Defined Benefit Plan, Amortization of Regulatory Deferrals, Net	1
Defined Benefit Plan, Amounts That Will Be Amortized from Regulatory Assets (Liabilities) and Accumulated Other Comprehensive Income Loss In Next Fiscal Year	(5)
PacifiCorp [Member] | Regulatory Asset, Pension and Other Postretirement Costs [Member] | Domestic Pension Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Net Periodic Benefit Cost Not Yet Recognized, Before Tax	473	474		313
Defined Benefit Plan, Reconciliation of Amounts Not Yet Recognized As Components of Net Periodic Benefit Cost [Roll Forward]
Defined Benefit Plan, Net Unamortized Gain (Loss) Arising During Period, Before Tax	40	189
Defined Benefit Plan, Net Amortization Recognized in Net Periodic Benefit Cost Before Tax	(41)	(28)
Defined Benefit Plan, Net Periodic Benefit Cost Not Yet Recognized, Arising During Period, Before Tax	(1)	161
PacifiCorp [Member] | Regulatory Asset, Pension and Other Postretirement Costs [Member] | Domestic Other Postretirement Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Net Periodic Benefit Cost Not Yet Recognized, Before Tax	26	17		77
Defined Benefit Plan, Reconciliation of Amounts Not Yet Recognized As Components of Net Periodic Benefit Cost [Roll Forward]
Defined Benefit Plan, Net Unamortized Gain (Loss) Arising During Period, Before Tax	5	(58)
Defined Benefit Plan, Net Amortization Recognized in Net Periodic Benefit Cost Before Tax	4	(2)
Defined Benefit Plan, Net Periodic Benefit Cost Not Yet Recognized, Arising During Period, Before Tax	9	(60)
PacifiCorp [Member] | Accumulated Other Comprehensive Income (Loss) [Member] | Domestic Pension Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Net Periodic Benefit Cost Not Yet Recognized, Before Tax	19	22		$ 15
Defined Benefit Plan, Reconciliation of Amounts Not Yet Recognized As Components of Net Periodic Benefit Cost [Roll Forward]
Defined Benefit Plan, Net Unamortized Gain (Loss) Arising During Period, Before Tax	(2)	8
Defined Benefit Plan, Net Amortization Recognized in Net Periodic Benefit Cost Before Tax	(1)	(1)
Defined Benefit Plan, Net Periodic Benefit Cost Not Yet Recognized, Arising During Period, Before Tax	$ (3)	$ 7