Employee Benefit Plans Employee Benefit Plans - PacifiCorp - Employer Contributions (Details) $ in Millions	9 Months Ended
	Sep. 30, 2016 USD ($)
Domestic Pension Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, expected contributions in current fiscal year	$ 77
Employer contributions	73
Domestic Other Postretirement Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, expected contributions in current fiscal year	1
Employer contributions	1
PacifiCorp [Member] | Domestic Pension Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, expected contributions in current fiscal year	4
Employer contributions	3
PacifiCorp [Member] | Domestic Other Postretirement Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, expected contributions in current fiscal year	0
Employer contributions	$ 0