Cash and Cash Equivalents and Restricted Cash and Cash Equivalents - LLC (Details) - USD ($) $ in Millions	Jun. 30, 2021	Dec. 31, 2020	Jun. 30, 2020	Dec. 31, 2019
Condensed Cash Flow Statements, Captions [Line Items]
Cash and cash equivalents	$ 1,331	$ 1,290
Restricted cash and cash equivalents	154	140
Total cash and cash equivalents and restricted cash and cash equivalents	1,500	1,445	$ 2,070	$ 1,268
MidAmerican Funding, LLC
Condensed Cash Flow Statements, Captions [Line Items]
Cash and cash equivalents	31	39
Restricted cash and cash equivalents	8	7
Total cash and cash equivalents and restricted cash and cash equivalents	$ 39	$ 46	$ 35	$ 331