CONSOLIDATED STATEMENTS OF CASH FLOWS (Unaudited) (USD $)	9 Months Ended
	Sep. 30, 2011	Sep. 30, 2010
CASH FLOWS FROM OPERATING ACTIVITIES:
Net income	$ 188,680,000	$ 212,771,000	[1]
Adjustments to reconcile net income to net cash from operating activities:
Depreciation and amortization	266,445,000	249,067,000
Deferred taxes and deferred investment tax credit	99,920,000	126,659,000
AFUDC-equity	(12,854,000)	(20,915,000)
Deferred energy	(20,802,000)	134,969,000
Gain on sale of asset	0	(7,575,000)
Amortization of other regulatory assets	124,213,000	59,643,000
Deferred rate increase	65,306,000	(6,250,000)
Other, net	25,633,000	8,922,000
Changes in certain assets and liabilities:
Accounts receivable	(132,078,000)	(82,833,000)
Materials, supplies and fuel	(26,290,000)	5,883,000
Other current assets	(5,242,000)	475,000
Accounts payable	32,397,000	43,110,000
Accrued retirement benefits	167,000	(13,658,000)
Other current liabilities	(37,869,000)	(13,589,000)
Risk management assets and liabilities	1,913,000	10,086,000
Other deferred assets	(14,982,000)	(4,912,000)
Other regulatory assets	(72,480,000)	(41,679,000)
Other deferred liabilities	(15,043,000)	(4,850,000)
Net Cash from Operating Activities	467,034,000	655,324,000
CASH FLOWS FROM (USED BY) INVESTING ACTIVITIES:
Additions to utility plant (excluding AFUDC-equity)	(469,870,000)	(520,175,000)
Proceeds from sale of asset	166,603,000	18,225,000
Customer advances for construction	(7,159,000)	(6,030,000)
Contributions in aid of construction	79,343,000	46,217,000
Investments and other property - net	410,000	(9,090,000)
Net Cash used by Investing Activities	(230,673,000)	(470,853,000)
CASH FLOWS FROM (USED BY) FINANCING ACTIVITIES:
Proceeds from issuance of long-term debt	386,784,000	660,711,000
Retirement of long-term debt	(480,689,000)	(453,656,000)
Settlement of interest rate lock	(14,944,000)	0
Sale of common stock	8,681,000	4,086,000
Dividends paid	(84,907,000)	(77,561,000)
Net Cash from (used by) Financing Activities	(185,075,000)	133,580,000
Net Increase in Cash and Cash Equivalents	51,286,000	318,051,000
Beginning Balance in Cash and Cash Equivalents	86,189,000	62,706,000
Ending Balance in Cash and Cash Equivalents	137,475,000	380,757,000
Cash paid during period for:
Interest	251,011,000	264,974,000
Income taxes	1,000	14,000
Significant non-cash transactions:
Accrued construction expenses as of September 30,	158,849,000	65,163,000
Capital lease obligations incurred	0	15,336,000
Nevada Power Company [Member]
CASH FLOWS FROM OPERATING ACTIVITIES:
Net income	161,651,000	176,386,000
Adjustments to reconcile net income to net cash from operating activities:
Depreciation and amortization	186,798,000	169,330,000
Deferred taxes and deferred investment tax credit	85,488,000	90,930,000
AFUDC-equity	(10,979,000)	(18,555,000)
Deferred energy	14,651,000	99,407,000
Amortization of other regulatory assets	62,994,000	41,415,000
Deferred rate increase	65,306,000	(6,250,000)
Other, net	18,507,000	3,085,000
Changes in certain assets and liabilities:
Accounts receivable	(145,862,000)	(108,609,000)
Materials, supplies and fuel	(9,100,000)	4,678,000
Other current assets	(3,307,000)	233,000
Accounts payable	26,434,000	35,249,000
Accrued retirement benefits	3,971,000	(13,320,000)
Other current liabilities	(32,523,000)	(8,474,000)
Risk management assets and liabilities	1,382,000	7,903,000
Other deferred assets	(13,788,000)	(2,214,000)
Other regulatory assets	(44,383,000)	(28,175,000)
Other deferred liabilities	(16,676,000)	(3,233,000)
Net Cash from Operating Activities	350,564,000	439,786,000
CASH FLOWS FROM (USED BY) INVESTING ACTIVITIES:
Additions to utility plant (excluding AFUDC-equity)	(367,097,000)	(421,793,000)
Proceeds from sale of asset	31,997,000	3,254,000
Customer advances for construction	(2,165,000)	(3,891,000)
Contributions in aid of construction	64,617,000	42,034,000
Investments and other property - net	395,000	(99,000)
Net Cash used by Investing Activities	(272,253,000)	(380,495,000)
CASH FLOWS FROM (USED BY) FINANCING ACTIVITIES:
Proceeds from issuance of long-term debt	386,884,000	637,975,000
Retirement of long-term debt	(464,575,000)	(412,201,000)
Settlement of interest rate lock	(14,944,000)	0
Additional investment by parent company	54,000,000	0
Dividends paid	(65,000,000)	(62,000,000)
Net Cash from (used by) Financing Activities	(103,635,000)	163,774,000
Net Increase in Cash and Cash Equivalents	(25,324,000)	223,065,000
Beginning Balance in Cash and Cash Equivalents	60,077,000	42,609,000
Ending Balance in Cash and Cash Equivalents	34,753,000	265,674,000
Cash paid during period for:
Interest	182,992,000	180,732,000
Income taxes	1,000	2,000
Significant non-cash transactions:
Accrued construction expenses as of September 30,	141,384,000	57,638,000
Capital lease obligations incurred	0	15,336,000
Sierra Pacific Power Company [Member]
CASH FLOWS FROM OPERATING ACTIVITIES:
Net income	45,424,000	52,897,000
Adjustments to reconcile net income to net cash from operating activities:
Depreciation and amortization	79,647,000	79,737,000
Deferred taxes and deferred investment tax credit	23,296,000	21,134,000
AFUDC-equity	(1,875,000)	(2,360,000)
Deferred energy	(35,453,000)	35,562,000
Gain on sale of asset	0	(7,575,000)
Amortization of other regulatory assets	59,855,000	18,056,000
Other, net	8,015,000	4,454,000
Changes in certain assets and liabilities:
Accounts receivable	13,917,000	51,221,000
Materials, supplies and fuel	(17,190,000)	1,184,000
Other current assets	(964,000)	1,423,000
Accounts payable	12,833,000	1,112,000
Accrued retirement benefits	(4,504,000)	(1,939,000)
Other current liabilities	(6,447,000)	1,615,000
Risk management assets and liabilities	531,000	2,183,000
Other deferred assets	(1,194,000)	(2,698,000)
Other regulatory assets	(28,097,000)	(13,504,000)
Other deferred liabilities	(2,501,000)	(2,691,000)
Net Cash from Operating Activities	145,293,000	239,811,000
CASH FLOWS FROM (USED BY) INVESTING ACTIVITIES:
Additions to utility plant (excluding AFUDC-equity)	(102,773,000)	(111,476,000)
Proceeds from sale of asset	134,606,000	14,971,000
Customer advances for construction	(4,994,000)	(2,139,000)
Contributions in aid of construction	14,726,000	4,183,000
Investments and other property - net	15,000	(119,000)
Net Cash used by Investing Activities	41,580,000	(94,580,000)
CASH FLOWS FROM (USED BY) FINANCING ACTIVITIES:
Proceeds from issuance of long-term debt	0	22,736,000
Retirement of long-term debt	(16,114,000)	(41,308,000)
Dividends paid	(114,000,000)	(48,000,000)
Net Cash from (used by) Financing Activities	(130,114,000)	(66,572,000)
Net Increase in Cash and Cash Equivalents	56,759,000	78,659,000
Beginning Balance in Cash and Cash Equivalents	9,552,000	14,359,000
Ending Balance in Cash and Cash Equivalents	66,311,000	93,018,000
Cash paid during period for:
Interest	45,632,000	48,990,000
Income taxes	0	12,000
Significant non-cash transactions:
Accrued construction expenses as of September 30,	$ 17,465,000	$ 7,525,000

[1] As discussed in Note 1, Summary of Significant Accounting Policies, net income and earnings per share basic and diluted were reduced from that previously reported by $5.2 million (net of taxes) and $0.02 per share (net of taxes), respectively.