Revenue from Contract with Customer - LLC (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	$ 15,081	$ 14,837	$ 14,972
Nonregulated Operation [Member] | Nonregulated products and services [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	1,528	1,404	1,360
Nonregulated Operation [Member] | Corporate and Other [Member] | MidAmerican Funding, LLC and Subsidiaries [Member] | Nonregulated products and services [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	$ 8	$ 2	$ 4