Short-Term Debt and Credit Facilities - PacifiCorp - Credit Facility (Details) $ in Millions		Dec. 31, 2019 USD ($)		Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)
Line of Credit Facility [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity	[1]	$ 9,412		$ 9,114
Short-term Debt	[1]	(3,214)		(2,516)
Line of Credit Facility, Amounts Supported	[1]	(629)		(543)
Line of Credit Facility, Remaining Borrowing Capacity	[1]	5,569		6,055
PacifiCorp [Member]
Line of Credit Facility [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity		1,200	[2]	1,200
Short-term Debt		(130)		(30)	$ (80)	$ (270)	$ (20)
Line of Credit Facility, Amounts Supported		(256)		(89)
Line of Credit Facility, Remaining Borrowing Capacity		$ 814		$ 1,081
PacifiCorp [Member] | Line of Credit [Member]
Line of Credit Facility [Line Items]
Debt, Weighted Average Interest Rate		2.05%		2.85%
Debt To Capitalization Ratio		0.65
PacifiCorp [Member] | Commercial Paper [Member]
Line of Credit Facility [Line Items]
Debt, Weighted Average Interest Rate		2.05%		2.85%
PacifiCorp [Member] | Unsecured credit facility, $600 million, expiring June 2022, first facility, extended [Member] | Line of Credit [Member]
Line of Credit Facility [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity		$ 600
PacifiCorp [Member] | Unsecured credit facility, $600 million, expiring June 2022, second facility, extended [Member] | Line of Credit [Member]
Line of Credit Facility [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity		600
PacifiCorp [Member] | Certain transactions required by third parties [Member]
Line of Credit Facility [Line Items]
Line of Credit Facility, Amounts Supported		(13)		$ (14)
PacifiCorp [Member] | Tax exempt bond obligations and commodity contract collateral requirement [Member]
Line of Credit Facility [Line Items]
Letters of Credit Outstanding, Amount		$ 13		$ 184

[1] (1)The table does not include unused credit facilities and letters of credit for investments that are accounted for under the equity method.

[2] (2) Includes the drawn uncommitted credit facilities totaling $39 million at Northern Powergrid.