Employee Benefit Plans - MEC - Funded Status (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]
Defined Benefit Plan, Benefit Obligation, Increase (Decrease) for Plan Amendment	$ 0	$ 8
Other Postretirement Benefits Plan [Member]
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Beginning balance	664	736
Defined Benefit Plan, Plan Assets, Contributions by Employer	2	8
Defined Benefit Plan, Contributions by Plan Participants (Deprecated 2017-01-31)	9	8
Defined Benefit Plan, Plan Assets, Increase (Decrease) for Actual Return (Loss)	122	(38)
Defined Benefit Plan, Plan Assets, Payment for Settlement	0	0
Defined Benefit Plan, Benefits Paid (Deprecated 2017-01-31)	(55)	(50)
Ending balance	742	664	$ 736
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]
Beginning balance	672	721
Defined Benefit Plan, Service Cost	8	9	9
Defined Benefit Plan, Interest Cost	27	24	29
Defined Benefit Plan, Contributions by Plan Participants (Deprecated 2017-01-31)	9	8
Defined Benefit Plan, Benefit Obligation, Actuarial Gain (Loss)	12	(40)
Defined Benefit Plan, Benefit Obligation, Increase (Decrease) for Plan Amendment	0	0
Defined Benefit Plan, Benefit Obligation, Payment for Settlement	0	0
Defined Benefit Plan, Benefits Paid (Deprecated 2017-01-31)	(55)	(50)
Ending balance	673	672	721
Defined Benefit Plan, Funded (Unfunded) Status of Plan [Abstract]
Defined Benefit Plan, Funded (Unfunded) Status of Plan	69	(8)
Assets for Plan Benefits, Defined Benefit Plan	76	5
Other current liabilities	0	0
Liability, Defined Benefit Plan, Noncurrent	(7)	(13)
Defined Benefit Plan, Amounts for Asset (Liability) Recognized in Statement of Financial Position	69	(8)
Supplemental Employee Retirement Plan [Member]
Defined Benefit Plans, Supplemental Employee Retirement Plans [Abstract]
Life Insurance, Corporate or Bank Owned, Amount	252	256
MidAmerican Energy Company [Member]
Defined Benefit Plans, Supplemental Employee Retirement Plans [Abstract]
Life Insurance, Corporate or Bank Owned, Amount	203	191
MidAmerican Energy Company [Member] | Pension Plan [Member]
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Beginning balance	644
Ending balance	717	644
MidAmerican Energy Company [Member] | Other Postretirement Benefits Plan [Member]
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Beginning balance	247	277
Defined Benefit Plan, Plan Assets, Contributions by Employer	1	1
Defined Benefit Plan, Contributions by Plan Participants (Deprecated 2017-01-31)	2	1
Defined Benefit Plan, Plan Assets, Increase (Decrease) for Actual Return (Loss)	42	(17)
Defined Benefit Plan, Benefits Paid (Deprecated 2017-01-31)	(20)	(15)
Ending balance	272	247	277
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]
Beginning balance	242	246
Defined Benefit Plan, Service Cost	5	5	5
Defined Benefit Plan, Interest Cost	10	8	9
Defined Benefit Plan, Contributions by Plan Participants (Deprecated 2017-01-31)	2	1
Defined Benefit Plan, Benefit Obligation, Actuarial Gain (Loss)	(13)	(3)
Defined Benefit Plan, Benefits Paid (Deprecated 2017-01-31)	(20)	(15)
Ending balance	226	242	246
Defined Benefit Plan, Funded (Unfunded) Status of Plan [Abstract]
Defined Benefit Plan, Funded (Unfunded) Status of Plan	46	5
Assets for Plan Benefits, Defined Benefit Plan	46	5
Other current liabilities	0	0
Liability, Defined Benefit Plan, Noncurrent	0	0
Defined Benefit Plan, Amounts for Asset (Liability) Recognized in Statement of Financial Position	46	5
MidAmerican Energy Company [Member] | MidAmerican Energy Company [Member] | Supplemental Employee Retirement Plan [Member]
Defined Benefit Plans, Supplemental Employee Retirement Plans [Abstract]
Life Insurance, Corporate or Bank Owned, Amount	122	116
UNITED STATES | Pension Plan [Member]
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Beginning balance	2,396	2,761
Defined Benefit Plan, Plan Assets, Contributions by Employer	12	38
Defined Benefit Plan, Contributions by Plan Participants (Deprecated 2017-01-31)	0	0
Defined Benefit Plan, Plan Assets, Increase (Decrease) for Actual Return (Loss)	456	(147)
Defined Benefit Plan, Plan Assets, Payment for Settlement	(22)	(119)
Defined Benefit Plan, Benefits Paid (Deprecated 2017-01-31)	(186)	(137)
Ending balance	2,656	2,396	2,761
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]
Beginning balance	2,718	3,006
Defined Benefit Plan, Service Cost	16	21	24
Defined Benefit Plan, Interest Cost	111	105	116
Defined Benefit Plan, Contributions by Plan Participants (Deprecated 2017-01-31)	0	0
Defined Benefit Plan, Benefit Obligation, Actuarial Gain (Loss)	242	(160)
Defined Benefit Plan, Benefit Obligation, Increase (Decrease) for Plan Amendment	(1)	2
Defined Benefit Plan, Benefit Obligation, Payment for Settlement	22	119
Defined Benefit Plan, Benefits Paid (Deprecated 2017-01-31)	(186)	(137)
Ending balance	2,878	2,718	3,006
Defined Benefit Plan, Accumulated Benefit Obligation	2,867	2,709
Defined Benefit Plan, Funded (Unfunded) Status of Plan [Abstract]
Defined Benefit Plan, Funded (Unfunded) Status of Plan	(222)	(322)
Assets for Plan Benefits, Defined Benefit Plan	73	20
Other current liabilities	(13)	(13)
Liability, Defined Benefit Plan, Noncurrent	(282)	(329)
Defined Benefit Plan, Amounts for Asset (Liability) Recognized in Statement of Financial Position	(222)	(322)
UNITED STATES | MidAmerican Energy Company [Member] | Pension Plan [Member]
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Beginning balance	644	745
Defined Benefit Plan, Plan Assets, Contributions by Employer	7	7
Defined Benefit Plan, Contributions by Plan Participants (Deprecated 2017-01-31)	0	0
Defined Benefit Plan, Plan Assets, Increase (Decrease) for Actual Return (Loss)	123	(39)
Defined Benefit Plan, Plan Assets, Payment for Settlement	0	(37)
Defined Benefit Plan, Benefits Paid (Deprecated 2017-01-31)	(57)	(32)
Ending balance	717	644	745
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]
Beginning balance	736	799
Defined Benefit Plan, Service Cost	6	9	9
Defined Benefit Plan, Interest Cost	30	28	31
Defined Benefit Plan, Contributions by Plan Participants (Deprecated 2017-01-31)	0	0
Defined Benefit Plan, Benefit Obligation, Actuarial Gain (Loss)	48	(33)
Defined Benefit Plan, Benefit Obligation, Increase (Decrease) for Plan Amendment	0	2
Defined Benefit Plan, Benefit Obligation, Payment for Settlement	0	(37)
Defined Benefit Plan, Benefits Paid (Deprecated 2017-01-31)	(57)	(32)
Ending balance	763	736	$ 799
Defined Benefit Plan, Accumulated Benefit Obligation	758	733
Defined Benefit Plan, Funded (Unfunded) Status of Plan [Abstract]
Defined Benefit Plan, Funded (Unfunded) Status of Plan	(46)	(92)
Assets for Plan Benefits, Defined Benefit Plan	66	17
Other current liabilities	(7)	(7)
Liability, Defined Benefit Plan, Noncurrent	(105)	(102)
Defined Benefit Plan, Amounts for Asset (Liability) Recognized in Statement of Financial Position	(46)	(92)
UNITED STATES | MidAmerican Energy Company [Member] | Supplemental Employee Retirement Plan [Member]
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]
Beginning balance	109
Ending balance	112	109
Defined Benefit Plan, Accumulated Benefit Obligation	$ 112	$ 109