Risk Management and Hedging Activities (MEC) Balance Sheet Location (Details) (MidAmerican Energy Company [Member], Commodity Contract [Member], USD $) In Millions, unless otherwise specified	Jun. 30, 2014		Mar. 31, 2014	Dec. 31, 2013		Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012
Derivatives, Fair Value [Line Items]
Total derivative assets (liabilities), net	$ (20)			$ (27)
Cash collateral, net receivable (payable), offset against derivatives	38			0
Total derivatives - net of collateral	18			(27)
Current Assets - Other [Member]
Derivatives, Fair Value [Line Items]
Total derivative assets (liabilities), net	19			2
Cash collateral, net receivable (payable), offset against derivatives	(1)			(2)
Total derivatives - net of collateral	18			0
Other Assets - Other [Member]
Derivatives, Fair Value [Line Items]
Total derivative assets (liabilities), net	6			2
Cash collateral, net receivable (payable), offset against derivatives	0			0
Total derivatives - net of collateral	6			2
Current Liabilities - Other [Member]
Derivatives, Fair Value [Line Items]
Total derivative assets (liabilities), net	(41)			(20)
Cash collateral, net receivable (payable), offset against derivatives	36			1
Total derivatives - net of collateral	(5)			(19)
Other Liabilities - Other [Member]
Derivatives, Fair Value [Line Items]
Total derivative assets (liabilities), net	(4)			(11)
Cash collateral, net receivable (payable), offset against derivatives	3			1
Total derivatives - net of collateral	(1)			(10)
Not Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Commodity assets	39	[1]		23	[1]
Commodity liabilities	(86)	[1]		(40)	[1]
Total derivative assets (liabilities), net	(47)	[1]		(17)	[1]
Net regulatory asset	48		32	10		23	24	45
Not Designated as Hedging Instrument [Member] | Current Assets - Other [Member]
Derivatives, Fair Value [Line Items]
Commodity assets	0	[1]		3	[1]
Commodity liabilities	(1)	[1]		(1)	[1]
Total derivative assets (liabilities), net	(1)	[1]		2	[1]
Not Designated as Hedging Instrument [Member] | Other Assets - Other [Member]
Derivatives, Fair Value [Line Items]
Commodity assets	1	[1]		3	[1]
Commodity liabilities	(1)	[1]		(1)	[1]
Total derivative assets (liabilities), net	0	[1]		2	[1]
Not Designated as Hedging Instrument [Member] | Current Liabilities - Other [Member]
Derivatives, Fair Value [Line Items]
Commodity assets	37	[1]		16	[1]
Commodity liabilities	(79)	[1]		(32)	[1]
Total derivative assets (liabilities), net	(42)	[1]		(16)	[1]
Not Designated as Hedging Instrument [Member] | Other Liabilities - Other [Member]
Derivatives, Fair Value [Line Items]
Commodity assets	1	[1]		1	[1]
Commodity liabilities	(5)	[1]		(6)	[1]
Total derivative assets (liabilities), net	(4)	[1]		(5)	[1]
Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Commodity assets	33			2
Commodity liabilities	(6)			(12)
Total derivative assets (liabilities), net	27			(10)
Designated as Hedging Instrument [Member] | Current Assets - Other [Member]
Derivatives, Fair Value [Line Items]
Commodity assets	21			1
Commodity liabilities	(1)			(1)
Total derivative assets (liabilities), net	20			0
Designated as Hedging Instrument [Member] | Other Assets - Other [Member]
Derivatives, Fair Value [Line Items]
Commodity assets	9			0
Commodity liabilities	(3)			0
Total derivative assets (liabilities), net	6			0
Designated as Hedging Instrument [Member] | Current Liabilities - Other [Member]
Derivatives, Fair Value [Line Items]
Commodity assets	2			1
Commodity liabilities	(1)			(5)
Total derivative assets (liabilities), net	1			(4)
Designated as Hedging Instrument [Member] | Other Liabilities - Other [Member]
Derivatives, Fair Value [Line Items]
Commodity assets	1			0
Commodity liabilities	(1)			(6)
Total derivative assets (liabilities), net	$ 0			$ (6)

[1] MidAmerican Energy's commodity derivatives not designated as hedging contracts are generally included in regulated rates, and as of June 30, 2014 and December 31, 2013, a net regulatory asset of $48 million and $10 million, respectively, was recorded related to the net derivative liability of $47 million and $17 million, respectively.