Short-Term Debt and Credit Facilities - MEC - Credit Facility (Details) $ in Millions		Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)
Line of Credit Facility [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity	[1]	$ 11,030	$ 9,412
Short-term Debt	[1]	(2,286)	(3,214)
Line of Credit Facility, Amounts Supported	[1]	(590)	(629)
Line of Credit Facility, Remaining Borrowing Capacity	[1]	8,154	5,569
MidAmerican Energy Company [Member]
Line of Credit Facility [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity		1,505	1,305
Line of Credit Facility, Amounts Supported		(370)	(370)
Line of Credit Facility, Remaining Borrowing Capacity		$ 1,135	935
MidAmerican Energy Company [Member] | Line of Credit [Member]
Line of Credit Facility [Line Items]
Debt To Capitalization Ratio		0.65
MidAmerican Energy Company [Member] | Commercial Paper [Member]
Line of Credit Facility [Line Items]
Regulatory Approval for Additional Short-Term Debt Issuances		$ 1,500
MidAmerican Energy Company [Member] | Unsecured credit facility, $900 million, expiring June 2022 [Member] | Line of Credit [Member]
Line of Credit Facility [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity		900
MidAmerican Energy Company [Member] | Unsecured credit facility, $400 million, expiring August 2020 [Member] | Line of Credit [Member]
Line of Credit Facility [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity		600
MidAmerican Energy Company [Member] | Unsecured 364-day Credit Facility, $5 million, expiring June [Member] | Line of Credit [Member]
Line of Credit Facility [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity		5
MidAmerican Energy Company [Member] | Unsecured credit facility, $400 million, expiring November 2019 [Member] | Line of Credit [Member]
Line of Credit Facility [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity			$ 400
MidAmerican Energy Company [Member] | Unsecured credit facility, $600 million, expiring May 2021 | Line of Credit [Member]
Line of Credit Facility [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity		$ 600

[1] The table does not include unused credit facilities and letters of credit for investments that are accounted for under the equity method.