Commitments and Contingencies - Commitments (Details) $ in Millions	3 Months Ended
	Mar. 31, 2017 USD ($)
PacifiCorp [Member] | Klamath Hydroelectric System [Member]
ContractualObligationFiscalYearMaturityScheduleTable [Line Items]
Dam removal cost limit	$ 200
PacifiCorp [Member] | Klamath Hydroelectric System [Member] | OREGON
ContractualObligationFiscalYearMaturityScheduleTable [Line Items]
Dam removal cost limit	184
PacifiCorp [Member] | Klamath Hydroelectric System [Member] | CALIFORNIA
ContractualObligationFiscalYearMaturityScheduleTable [Line Items]
Dam removal cost limit	16
Additional dam removal costs, California bond measure	250
Capital Addition Purchase Commitments [Member] | MidAmerican Energy Company [Member]
ContractualObligationFiscalYearMaturityScheduleTable [Line Items]
Purchase Obligation	$ 138