CONSOLIDATED STATEMENTS OF COMMON SHAREHOLDERS' EQUITY (Parenthetical) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Other Comprehensive Income (Loss), Pension and Other Postretirement Benefit Plans, Tax	$ (133)	$ (74)	$ (398)	$ (246)
Market value of risk management assets and liabilities	(154)	91	(261)	355
Unrealized net gain/(loss) on investments	(49)	0	(18)	0
Nevada Power Company
Other Comprehensive Income (Loss), Pension and Other Postretirement Benefit Plans, Tax	(52)	(33)	(156)	(103)
Sierra Pacific Power Company
Other Comprehensive Income (Loss), Pension and Other Postretirement Benefit Plans, Tax	$ (32)	$ (22)	$ (95)	$ (68)