Employee Benefit Plans Employee Benefit Plans - PacifiCorp (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Other Postretirement Benefits Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 3	$ 3	$ 5	$ 5
Interest cost	8	6	14	12
Expected return on plan assets	(10)	(12)	(20)	(22)
Net amortization	(1)	(3)	(3)	(6)
Net periodic benefit cost	0	(6)	(4)	(11)
PacifiCorp [Member] | Other Postretirement Benefits Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	1	1	1	1
Interest cost	3	3	6	6
Expected return on plan assets	(5)	(6)	(10)	(11)
Net amortization	0	(2)	0	(3)
Net periodic benefit cost	(1)	(4)	(3)	(7)
Domestic Plan [Member] | Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	4	5	8	10
Interest cost	28	26	55	52
Expected return on plan assets	(39)	(41)	(77)	(82)
Net amortization	7	7	16	15
Net periodic benefit cost	0	(3)	2	(5)
Domestic Plan [Member] | PacifiCorp [Member] | Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	0	0	0	0
Interest cost	11	10	22	21
Expected return on plan assets	(16)	(18)	(33)	(36)
Net amortization	3	4	6	7
Net periodic benefit cost	$ (2)	$ (4)	$ (5)	$ (8)