Employee Benefit Plans - PacifiCorp - Contributions and Benefit Payments (Details) $ in Millions	Dec. 31, 2018 USD ($)
Other Postretirement Benefits Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Expected Future Employer Contributions, Next Fiscal Year	$ 1
Defined Benefit Plan, Expected Future Benefit Payment, Next Twelve Months	53
Defined Benefit Plan, Expected Future Benefit Payment, Year Two	57
Defined Benefit Plan, Expected Future Benefit Payment, Year Three	55
Defined Benefit Plan, Expected Future Benefit Payment, Year Four	54
Defined Benefit Plan, Expected Future Benefit Payment, Year Five	53
Defined Benefit Plan, Expected Future Benefit Payment, Five Fiscal Years Thereafter	243
Other Postretirement Benefits Plan [Member] | PacifiCorp [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Expected Future Employer Contributions, Next Fiscal Year	0
Defined Benefit Plan, Expected Future Benefit Payment, Next Twelve Months	24
Defined Benefit Plan, Expected Future Benefit Payment, Year Two	26
Defined Benefit Plan, Expected Future Benefit Payment, Year Three	23
Defined Benefit Plan, Expected Future Benefit Payment, Year Four	22
Defined Benefit Plan, Expected Future Benefit Payment, Year Five	21
Defined Benefit Plan, Expected Future Benefit Payment, Five Fiscal Years Thereafter	95
Domestic Plan [Member] | Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Expected Future Employer Contributions, Next Fiscal Year	13
Defined Benefit Plan, Expected Future Benefit Payment, Next Twelve Months	221
Defined Benefit Plan, Expected Future Benefit Payment, Year Two	224
Defined Benefit Plan, Expected Future Benefit Payment, Year Three	221
Defined Benefit Plan, Expected Future Benefit Payment, Year Four	212
Defined Benefit Plan, Expected Future Benefit Payment, Year Five	212
Defined Benefit Plan, Expected Future Benefit Payment, Five Fiscal Years Thereafter	958
Domestic Plan [Member] | Pension Plan [Member] | PacifiCorp [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Expected Future Employer Contributions, Next Fiscal Year	4
Defined Benefit Plan, Expected Future Benefit Payment, Next Twelve Months	105
Defined Benefit Plan, Expected Future Benefit Payment, Year Two	102
Defined Benefit Plan, Expected Future Benefit Payment, Year Three	98
Defined Benefit Plan, Expected Future Benefit Payment, Year Four	92
Defined Benefit Plan, Expected Future Benefit Payment, Year Five	88
Defined Benefit Plan, Expected Future Benefit Payment, Five Fiscal Years Thereafter	$ 369