Discontinued Operations - MEC (Details) - MidAmerican Energy Company and Subsidiaries [Member] - Unregulated Retail Services [Member] - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2015	Dec. 31, 2015
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Discontinued Operations, Revenue	$ 224
Discontinued Operations, Cost of sales	212
Discontinued Operations, Cash flows from operations	$ 17
Discontinued Operations, Receivables		$ 115
Discontinued Operations, Derivative assets		41
Discontinued Operations, Deferred income tax assets, noncurrent		21
Discontinued Operations, Accounts payable		(49)
Discontinued Operations, Derivative liabilities		(42)
Discontinued Operations, Other assets and liabilities, net		4
Discontinued Operations, Net assets		90
Discontinued Operations, Accumulated other comprehensive loss, net		27
Discontinued Operations, Net assets and AOCI		$ 117