Consolidated Statements of Cash Flows - SPPC - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Net Income (Loss) Attributable to Parent	$ 513	$ 556
Allowance for equity funds	(21)	(17)
Deferred income taxes and amortization of investment tax credits	(166)	224
Changes in regulatory assets and liabilities	94	20
Other Noncash Income (Expense)	(19)	2
Trade receivables and other assets	250	308
Accrued property, income and other taxes	(60)	(187)
Accounts payable and other liabilities	(40)	(37)
Net cash flows from operating activities	1,479	1,438
Capital expenditures	(1,075)	(865)
Net cash flows from investing activities	(1,223)	(1,538)
Repayments of Long-term Debt	0	(200)
Net cash flows from financing activities	336	328
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents, Period Increase (Decrease), Excluding Exchange Rate Effect	593	229
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents	1,876	1,232
Sierra Pacific Power Company [Member]
Net Income (Loss) Attributable to Parent	34	24
Utilities Operating Expense, Depreciation and Amortization	30	28
Allowance for equity funds	(1)	(1)
Deferred income taxes and amortization of investment tax credits	6	13
Changes in regulatory assets and liabilities	12	3
Deferred Energy Change	13	(11)
Amortization of Deferred Charges	(4)	(21)
Other Noncash Income (Expense)	0	(2)
Trade receivables and other assets	3	20
Increase (Decrease) in Inventories	0	(3)
Accrued property, income and other taxes	(2)	(3)
Accounts payable and other liabilities	(16)	(63)
Net cash flows from operating activities	75	(12)
Capital expenditures	(45)	(41)
Net cash flows from investing activities	(45)	(41)
Proceeds from Issuance of Long-term Debt	0	6
Repayments of Long-term Debt	0	(1)
Payments of Ordinary Dividends, Common Stock	0	(2)
Net cash flows from financing activities	0	3
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents, Period Increase (Decrease), Excluding Exchange Rate Effect	30	(50)
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents	$ 38	$ 10