Employee Benefit Plans - MEC - Level 3 Rollforward (Details) - United States Pension Plan of US Entity [Member] - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2015		Dec. 31, 2014		Dec. 31, 2013	Dec. 31, 2012
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets		$ 2,489		$ 2,718		$ 2,711
Fair Value, Inputs, Level 3 [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	[1]	112		110
Real Estate Funds [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets		47		40
Real Estate Funds [Member] | Fair Value, Inputs, Level 3 [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets		47	[1]	40	[1]	31	$ 26
Defined Benefit Plan, Actual Return on Plan Assets Still Held		7		4		5
Defined Benefit Plan, Purchases, Sales, and Settlements		0		5		0
MidAmerican Energy Company [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets		678		730		722
MidAmerican Energy Company [Member] | Fair Value, Inputs, Level 3 [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets		47		40
MidAmerican Energy Company [Member] | Real Estate Funds [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets		47		40
MidAmerican Energy Company [Member] | Real Estate Funds [Member] | Fair Value, Inputs, Level 3 [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets		47		40		31	$ 26
Defined Benefit Plan, Actual Return on Plan Assets Still Held		7		4		5
Defined Benefit Plan, Purchases, Sales, and Settlements		$ 0		$ 5		$ 0

[1] Refer to Note 15 for additional discussion regarding the three levels of the fair value hierarchy.