Unaudited Quarterly Operating Results Unaudited Quarterly Operating Results (Notes)

12 Months Ended

Dec. 31, 2018

MidAmerican Energy Company [Member]

Quarterly Operating Results [Line Items]

Quarterly Financial Information [Text Block]

Unaudited Quarterly Operating Results (in millions)

	Three-Month Periods Ended
	March 31,		June 30,		September 30,		December 31,
	2018		2018		2018		2018
Operating revenue	$	746	$	717	$	832	$	754
Operating income	79		87		278		107
Net income (loss)	106		106		483		(13		)
	Three-Month Periods Ended
	March 31,		June 30,		September 30,		December 31,
	2017		2017		2017		2017
Operating revenue	$	695	$	658	$	813	$	671
Operating income	102		130		284		27
Net income	105		134		385		(19		)

Quarterly operating results are affected by, among other things, MidAmerican Energy's seasonal retail electricity prices, the timing of recognition of federal renewable electricity production tax credits related to MidAmerican Energy's wind-powered generating facilities and the seasonal impact of weather on electricity and natural gas sales.

MidAmerican Funding, LLC and Subsidiaries [Domain]

Quarterly Operating Results [Line Items]

Quarterly Financial Information [Text Block]

Unaudited Quarterly Operating Results (in millions)

	Three-Month Periods Ended
	March 31,		June 30,		September 30,		December 31,
	2018		2018		2018		2018
Operating revenue	$	747	$	718	$	832	$	756
Operating income	79		87		278		106
Net income (loss)	103		103		479		(16		)

	Three-Month Periods Ended
	March 31,		June 30,		September 30,		December 31,
	2017		2017		2017		2017
Operating revenue	$	696	$	659	$	815	$	676
Operating income	102		131		284		27
Net income	102		131		383		(42		)

Quarterly operating results are affected by, among other things, MidAmerican Energy's seasonal retail electricity prices, the timing of recognition of federal renewable electricity production tax credits related to MidAmerican Energy's wind-powered generating facilities and the seasonal impact of weather on electricity and natural gas sales.

Nevada Power Company [Member]

Quarterly Operating Results [Line Items]

Quarterly Financial Information [Text Block]

Unaudited Quarterly Operating Results (in millions)

	Three-Month Periods Ended
	March 31,		June 30,		September 30,		December 31,
	2018		2018		2018		2018
Operating revenues	$	395	$	562	$	820	$	407
Operating income	40		122		247		37
Net income	—		64		164		(2		)
	Three-Month Periods Ended
	March 31,		June 30,		September 30,		December 31,
	2017		2017		2017		2017
Operating revenues	$	392	$	574	$	819	$	421
Operating income	52		157		317		37
Net income	10		77		176		(8		)

Sierra Pacific Power Company [Member]

Quarterly Operating Results [Line Items]

Quarterly Financial Information [Text Block]

Unaudited Quarterly Operating Results (in millions)

	Three-Month Periods Ended
	March 31,		June 30,		September 30,		December 31,
	2018		2018		2018		2018
Regulated electric operating revenue	$	181	$	169	$	225	$	177
Regulated natural gas operating revenue	41		19		14		29
Operating income	47		19		56		30
Net income	34		7		35		16
	Three-Month Periods Ended
	March 31,		June 30,		September 30,		December 31,
	2017		2017		2017		2017
Regulated electric operating revenue	$	159	$	160	$	215	$	179
Regulated natural gas operating revenue	34		17		15		33
Operating income	46		36		75		41
Net income	24		17		44		24