SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Tables)

12 Months Ended

Dec. 31, 2011

Accounting Policies [Abstract]

Gross Utility Property and CWIP

		2011						2010
		NVE		NPC		SPPC		NVE		NPC		SPPC
Electric Generation assets		$	4,791	$	3,724	$	1,067	$	4,056	$	2,991	$	1,065
Electric Transmission assets			1,853		1,183		670		1,840		1,183		657
Electric Distribution assets			4,108		2,874		1,234		4,019		2,820		1,199
Electric General, Intangible plant			659		564		95		657		558		99
Electric CWIP			473		353		121		906		825		81
Natural Gas Distribution assets			312		-		312		303		-		303
Natural Gas General, Intangible plant			3		-		3		3		-		3
Natural Gas CWIP			14		-		14		2		-		2
Common Assets			197		-		197		191		-		191
	Total Utility Property, Gross	$	12,411	$	8,698	$	3,713	$	11,977	$	8,377	$	3,600

Average Estimated Use Life for Major Class of Utility Property, Plant, and Equipment

	Estimated Useful Lives
	NPC	SPPC
Electric Generation	25 to 125 years	25 to 125 years
Electric Transmission	45 to 65 years	50 to 70 years
Electric Distribution	20 to 65 years	30 to 65 years
Gas Distribution	N/A	40 to 70 years
General Plant	5 to 65 years	5 to 65 years

Schedule of Change in Asset Retirement Obligation [Table Text Block]

		NVE				NPC				SPPC
		2011		2010		2011		2010		2011		2010
ARO balance at January 1	$	55,202	$	55,968	$	47,126	$	48,320	$	8,076	$	7,648
Liabilities incurred in current period		3,282		-		3,282		-		-		-
Liabilities settled in current period		(6,996)		(34)		(6,996)		(34)		-		-
Accretion expense		3,866		3,877		3,348		3,383		518		494
Revision in estimated cash flows		16,391		(4,606)		15,021		(4,540)		1,370		(66)
Gain/Loss on settlement		(763)		(3)		(763)		(3)		-		-
ARO balance at December 31	$	70,982	$	55,202	$	61,018	$	47,126	$	9,964	$	8,076