Short-Term Debt and Credit Facilities - MidAmerican Funding (Details) - USD ($) $ in Millions		Dec. 31, 2020	Dec. 31, 2019
Line of Credit Facility [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity	[1]	$ 11,030	$ 9,412
MidAmerican Funding, LLC and Subsidiaries [Member] | Unsecured 364-day credit facility, $4 million, expiring June [Member] | MHC, Inc. [Member] | Line of Credit [Member]
Line of Credit Facility [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity		$ 4

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