Income Taxes (Notes)

12 Months Ended

Dec. 31, 2017

Schedule of Effective Income Tax Rate Reconciliation [Line Items]

Income Taxes [Text Block]

Income Taxes

Tax Cuts and Jobs Act

The 2017 Tax Reform impacts many areas of income tax law. The most material items include the reduction of the federal corporate tax rate from 35% to 21% effective January 1, 2018, the one-time repatriation tax of foreign earnings and profits and limitations on bonus depreciation for utility property. GAAP requires the effect on deferred tax assets and liabilities of a change in tax rates be recognized in the period the tax rate change was enacted. As a result of the 2017 Tax Reform, the Company reduced deferred income tax liabilities $7,115 million. As it is probable the change in deferred taxes for the Company's regulated businesses will be passed back to customers through regulatory mechanisms, the Company increased net regulatory liabilities by $5,950 million. The reduction in deferred income tax liabilities also resulted in a decrease in deferred income tax expense of $1,150 million, mostly driven by the Company's non-regulated businesses, primarily BHE Renewables, BHE's investment in BYD Company Limited and HomeServices.

As a result of the 2017 Tax Reform, BHE's consolidated net income increased by $516 million primarily due to benefits from reductions in deferred income tax liabilities of $1,150 million, partially offset by an accrual for the deemed repatriation of undistributed foreign earnings and profits totaling $419 million and equity earnings charges totaling $228 million mainly for amounts to be returned to the customers of equity investments in regulated entities.

In December 2017, the Securities and Exchange Commission issued Staff Accounting Bulletin ("SAB") 118 to assist in the implementation process of the 2017 Tax Reform by allowing for calculations to be classified as provisional and subject to remeasurement. There are three different classifications for the accounting: (1) completed, (2) not complete but reasonably estimable or (3) not complete and amounts are not reasonably estimable. The Company has recorded the impacts of the 2017 Tax Reform and believes all the impacts to be complete with the exception of the repatriation tax on foreign earnings and interpretations of the bonus depreciation rules. The Company has determined the amounts recorded and the interpretations relating to these two items to be provisional and subject to remeasurement during the measurement period upon obtaining the necessary additional information to complete the accounting. The Company believes the estimates for the repatriation tax to be reasonable, however, additional time is required to validate the inputs to the foreign earnings and profits calculation, the basis on which the repatriation tax is determined, and additional guidance is required to determine state income tax implications. The Company also believes its interpretations for bonus depreciation to be reasonable, however, as the guidance is clarified estimates may change. The accounting is estimated to be completed by December 2018.

Income tax (benefit) expense consists of the following for the years ended December 31 (in millions):

	2017			2016			2015
Current:
Federal	$	(653	)	$	(743	)	$	(929	)
State	(3		)	1			29
Foreign	83			55			84
	(573		)	(687		)	(816		)
Deferred:
Federal	(76		)	1,164			1,310
State	100			(59		)	(53		)
Foreign	2			(7		)	17
	26			1,098			1,274
Investment tax credits	(7		)	(8		)	(8		)
Total	$	(554	)	$	403		$	450

A reconciliation of the federal statutory income tax rate to the effective income tax rate applicable to income before income tax (benefit) expense is as follows for the years ended December 31:

	2017		2016		2015
Federal statutory income tax rate	35	%	35	%	35	%
Income tax credits	(20	)	(14	)	(11	)
State income tax, net of federal income tax benefit	3		(1	)	(1	)
Effects of tax rate change and repatriation tax	(31	)	—		—
Income tax effect of foreign income	(5	)	(6	)	(7	)
Equity income	(2	)	2		2
Other, net	(2	)	(2	)	(2	)
Effective income tax rate	(22	)%	14	%	16	%

Effects of 2017 Tax Reform have been included in state income tax, net of federal income tax benefit, effects of tax rate change and repatriation tax and equity income.

Income tax credits relate primarily to production tax credits from wind-powered generating facilities owned by MidAmerican Energy, PacifiCorp and BHE Renewables. Federal renewable electricity production tax credits are earned as energy from qualifying wind-powered generating facilities is produced and sold and are based on a per-kilowatt hour rate pursuant to the applicable federal income tax law. Wind-powered generating facilities are eligible for the credits for 10 years from the date the qualifying generating facilities are placed in-service.

Income tax effect of foreign income includes, among other items, deferred income tax benefits of $16 million in 2016 and $39 million in 2015 related to the enactment of reductions in the United Kingdom corporate income tax rate. In September 2016, the corporate income tax rate was reduced from 18% to 17% effective April 1, 2020. In November 2015, the corporate income tax rate was reduced from 20% to 19% effective April 1, 2017, with a further reduction to 18% effective April 1, 2020.

Berkshire Hathaway includes the Company in its United States federal income tax return. As of December 31, 2017, the Company had current income taxes receivable from Berkshire Hathaway of $334 million. As of December 31, 2016, the Company had current income taxes payable to Berkshire Hathaway of $27 million.

The net deferred income tax liability consists of the following as of December 31 (in millions):

	2017			2016
Deferred income tax assets:
Regulatory liabilities	$	1,707		$	909
Federal, state and foreign carryforwards	1,118			987
AROs	223			326
Employee benefits	45			209
Derivative contracts	2			29
Other	448			707
Total deferred income tax assets	3,543			3,167
Valuation allowances	(126		)	(64		)
Total deferred income tax assets, net	3,417			3,103
Deferred income tax liabilities:
Property-related items	(9,950		)	(14,237		)
Investments	(843		)	(962		)
Regulatory assets	(651		)	(1,449		)
Other	(215		)	(334		)
Total deferred income tax liabilities	(11,659		)	(16,982		)
Net deferred income tax liability	$	(8,242	)	$	(13,879	)

The following table provides the Company's net operating loss and tax credit carryforwards and expiration dates as of December 31, 2017 (in millions):

	Federal		State		Foreign		Total
Net operating loss carryforwards(1)	$	172	$	10,813	$	605	$	11,590
Deferred income taxes on net operating loss carryforwards	$	37	$	858	$	163	$	1,058
Expiration dates	2023-2025		2018-2037		2035-2037
Tax credits	$	31	$	29	$	—	$	60
Expiration dates	2023- indefinite		2018- indefinite

(1) The federal net operating loss carryforwards relate principally to net operating loss carryforwards of subsidiaries that are tax residents in both the United States and the United Kingdom. The federal net operating loss carryforwards were generated prior to Berkshire Hathaway Inc.'s ownership and will begin to expire in 2023.

The United States Internal Revenue Service has closed its examination of the Company's income tax returns through December 31, 2009. State tax agencies have closed their examinations of, or the statute of limitations has expired for, the Company's income tax returns through December 31, 2005, for California and Utah, through December 31, 2007 for Kansas and Minnesota, through December 31, 2008 for Illinois, through December 31, 2009 for Idaho, Montana, Nebraska and Oregon and through December 31, 2013 for Iowa. The closure of examinations, or the expiration of the statute of limitations, for state filings may not preclude the state from adjusting the state net operating loss carryforward utilized in a year for which the examination is not closed.

A reconciliation of the beginning and ending balances of the Company's net unrecognized tax benefits is as follows for the years ended December 31 (in millions):

	2017			2016
Beginning balance	$	128		$	198
Additions based on tax positions related to the current year	6			7
Additions for tax positions of prior years	70			6
Reductions for tax positions of prior years	(18		)	(11		)
Statute of limitations	(4		)	(1		)
Settlements	(1		)	(67		)
Interest and penalties	—			(4		)
Ending balance	$	181		$	128

As of December 31, 2017 and 2016, the Company had unrecognized tax benefits totaling $158 million and $104 million, respectively, that if recognized, would have an impact on the effective tax rate. The remaining unrecognized tax benefits relate to tax positions for which ultimate deductibility is highly certain but for which there is uncertainty as to the timing of such deductibility. Recognition of these tax benefits, other than applicable interest and penalties, would not affect the Company's effective income tax rate.

PacifiCorp [Member]

Schedule of Effective Income Tax Rate Reconciliation [Line Items]

Income Taxes [Text Block]

Income Taxes

Tax Cuts and Jobs Act

The 2017 Tax Reform impacts many areas of income tax law. The most material items include the reduction of the federal corporate tax rate from 35% to 21% effective January 1, 2018 and limitations on bonus depreciation for utility property. GAAP requires the effect on deferred tax assets and liabilities of a change in tax rates be recognized in the period the tax rate change was enacted. As a result of the 2017 Tax Reform, PacifiCorp reduced deferred income tax liabilities $2,361 million. As it is probable the change in deferred taxes will be passed back to customers through regulatory mechanisms, PacifiCorp increased net regulatory liabilities by $2,358 million.

In December 2017, the Securities and Exchange Commission issued Staff Accounting Bulletin ("SAB") 118 to assist in the implementation process of the 2017 Tax Reform by allowing for calculations to be classified as provisional and subject to remeasurement. There are three different classifications for the accounting: (1) completed, (2) not complete but reasonably estimable or (3) not complete and amounts are not reasonably estimable. PacifiCorp has recorded the impacts of the 2017 Tax Reform and believes all the impacts to be complete with the exception of interpretations of the bonus depreciation rules. PacifiCorp has determined the amounts recorded and the interpretations relating to this item to be provisional and subject to remeasurement during the measurement period upon obtaining the necessary additional information to complete the accounting. PacifiCorp believes its interpretations for bonus depreciation to be reasonable, however, as the guidance is clarified estimates may change. The accounting is estimated to be completed by December 2018.

Income tax expense (benefit) consists of the following for the years ended December 31 (in millions):

	2017			2016			2015
Current:
Federal	$	249		$	169		$	130
State	41			32			26
Total	290			201			156
Deferred:
Federal	59			123			148
State	15			21			29
Total	74			144			177
Investment tax credits	(4		)	(5		)	(5		)
Total income tax expense	$	360		$	340		$	328

A reconciliation of the federal statutory income tax rate to the effective income tax rate applicable to income before income tax expense is as follows for the years ended December 31:

	2017		2016		2015
Federal statutory income tax rate	35	%	35	%	35	%
State income taxes, net of federal income tax benefit	3		3		3
Federal income tax credits	(5	)	(6	)	(6	)
Other	(1	)	(1	)	—
Effective income tax rate	32	%	31	%	32	%

Income tax credits relate primarily to production tax credits earned by PacifiCorp's wind-powered generating facilities. Federal renewable electricity production tax credits are earned as energy from qualifying wind-powered generating facilities is produced and sold and are based on a per-kilowatt hour rate pursuant to the applicable federal income tax law. Wind-powered generating facilities are eligible for the credits for 10 years from the date the qualifying generating facilities are placed in-service.

The net deferred income tax liability consists of the following as of December 31 (in millions):

	2017			2016
Deferred income tax assets:
Regulatory liabilities	$	756		$	393
Employee benefits	84			202
Derivative contracts and unamortized contract values	48			67
State carryforwards	83			69
Asset retirement obligations	50			78
Other	50			94
	1,071			903
Deferred income tax liabilities:
Property, plant and equipment	(3,381		)	(5,161		)
Regulatory assets	(261		)	(586		)
Other	(11		)	(36		)
	(3,653		)	(5,783		)
Net deferred income tax liability	$	(2,582	)	$	(4,880	)

The following table provides PacifiCorp's net operating loss and tax credit carryforwards and expiration dates as of December 31, 2017 (in millions):

	State
Net operating loss carryforwards	$	1,356
Deferred income taxes on net operating loss carryforwards	$	63
Expiration dates	2018 - 2032
Tax credit carryforwards	$	20
Expiration dates	2018 - indefinite

The United States Internal Revenue Service has closed its examination of PacifiCorp's income tax returns through December 31, 2009. The statute of limitations for PacifiCorp's state income tax returns have expired through December 31, 2009, with the exception of California and Utah, for which the statute of limitations have expired through March 31, 2006. The statute of limitations expiring for state filings may not preclude the state from adjusting the state net operating loss carryforward utilized in a year for which the examination is not closed.

As of December 31, 2017 and 2016, PacifiCorp had unrecognized tax benefits totaling $10 million and $12 million, respectively, related to tax positions for which ultimate deductibility is highly certain but for which there is uncertainty as to the timing of such deductibility. Recognition of these tax benefits, other than applicable interest and penalties, would not affect PacifiCorp's effective income tax rate.

MidAmerican Energy Company [Member]

Schedule of Effective Income Tax Rate Reconciliation [Line Items]

Income Taxes [Text Block]

Income Taxes

Tax Cuts and Jobs Act

The 2017 Tax Reform impacts many areas of income tax law. The most material items include the reduction of the federal corporate tax rate from 35% to 21% effective January 1, 2018 and limitations on bonus depreciation for utility property. GAAP requires the effect on deferred tax assets and liabilities of a change in tax rates be recognized in the period the tax rate change was enacted. As a result of the 2017 Tax Reform, MidAmerican Energy reduced deferred income tax liabilities $1,824 million. As it is probable the change in deferred taxes will be passed back to customers through regulatory mechanisms, MidAmerican Energy increased net regulatory liabilities by $1,845 million.

In December 2017, the Securities and Exchange Commission issued Staff Accounting Bulletin ("SAB") 118 to assist in the implementation process of the 2017 Tax Reform by allowing for calculations to be classified as provisional and subject to remeasurement. There are three different classifications for the accounting: (1) completed, (2) not complete but reasonably estimable or (3) not complete and amounts are not reasonably estimable. MidAmerican Energy has recorded the impacts of 2017 Tax Reform and believes all the impacts to be complete with the exception of interpretations of the bonus depreciation rules. MidAmerican Energy has determined the amounts recorded and the interpretations relating to this item to be provisional and subject to remeasurement during the measurement period upon obtaining the necessary additional information to complete the accounting. MidAmerican Energy believes its interpretations for bonus depreciation to be reasonable; however, as the guidance is clarified estimates may change. The accounting is estimated to be completed by December 2018.

MidAmerican Energy's income tax benefit from continuing operations consists of the following for the years ended December 31 (in millions):

	2017			2016			2015
Current:
Federal	$	(490	)	$	(479	)	$	(415	)
State	(25		)	(14		)	(6		)
	(515		)	(493		)	(421		)
Deferred:
Federal	335			366			281
State	(2		)	(4		)	(6		)
	333			362			275
Investment tax credits	(1		)	(1		)	(1		)
Total	$	(183	)	$	(132	)	$	(147	)

A reconciliation of the federal statutory income tax rate to MidAmerican Energy's effective income tax rate applicable to income before income tax benefit from continuing operations is as follows for the years ended December 31:

	2017		2016		2015
Federal statutory income tax rate	35	%	35	%	35	%
Income tax credits	(68	)	(61	)	(71	)
State income tax, net of federal income tax benefit	(4	)	(3	)	(2	)
Effects of ratemaking	(7	)	(3	)	(12	)
2017 Tax Reform	2		—		—
Other, net	(1	)	—		1
Effective income tax rate	(43	)%	(32	)%	(49	)%

Income tax credits relate primarily to production tax credits earned by MidAmerican Energy's wind-powered generating facilities. Federal renewable electricity production tax credits are earned as energy from qualifying wind-powered generating facilities is produced and sold and are based on a per-kilowatt hour rate pursuant to the applicable federal income tax law. Interim recognition of production tax credits in income is based on the annualized effective tax rate applied each period, similar to all book to tax differences. Recognition of production tax credits in income during interim periods of the year may vary significantly from actual amounts earned. Wind-powered generating facilities are eligible for the credits for 10 years from the date the qualifying generating facilities are placed in service.

MidAmerican Energy's net deferred income tax liability consists of the following as of December 31 (in millions):

	2017			2016
Deferred income tax assets:
Regulatory liabilities	$	443		$	333
Asset retirement obligations	160			230
Employee benefits	45			66
Other	57			74
Total deferred income tax assets	705			703
Deferred income tax liabilities:
Depreciable property	(2,865		)	(3,763		)
Regulatory assets	(42		)	(471		)
Other	(35		)	(41		)
Total deferred income tax liabilities	(2,942		)	(4,275		)
Net deferred income tax liability	$	(2,237	)	$	(3,572	)

As of December 31, 2017, MidAmerican Energy has available $40 million of state tax carryforwards, principally related to $583 million of net operating losses, that expire at various intervals between 2018 and 2036.

The United States Internal Revenue Service has closed its examination of BHE's income tax returns through December 31, 2009, including components related to MidAmerican Energy. In addition, state jurisdictions have closed their examinations of MidAmerican Energy's income tax returns for Iowa through December 31, 2013, for Illinois through December 31, 2008, and for other jurisdictions through December 31, 2009.

A reconciliation of the beginning and ending balances of MidAmerican Energy's net unrecognized tax benefits is as follows for the years ended December 31 (in millions):

	2017			2016
Beginning balance	$	10		$	10
Additions based on tax positions related to the current year	1			—
Additions for tax positions of prior years	23			10
Reductions based on tax positions related to the current year	(4		)	(2		)
Reductions for tax positions of prior years	(19		)	(8		)
Interest and penalties	1			—
Ending balance	$	12		$	10

As of December 31, 2017, MidAmerican Energy had unrecognized tax benefits totaling$38 million that, if recognized, would have an impact on the effective tax rate. The remaining unrecognized tax benefits relate to tax positions for which ultimate deductibility is highly certain but for which there is uncertainty as to the timing of such deductibility. Recognition of these tax benefits, other than applicable interest and penalties, would not affect MidAmerican Energy's effective income tax rate.

MidAmerican Funding, LLC and Subsidiaries [Domain]

Schedule of Effective Income Tax Rate Reconciliation [Line Items]

Income Taxes [Text Block]

Income Taxes

Tax Cuts and Jobs Act

On December 22, 2017, the Tax Cuts and Jobs Act ("2017 Tax Reform") was signed into law, which impacts many areas of income tax law. The most material items include the reduction of the federal corporate tax rate from 35% to 21% effective January 1, 2018 and limitations on bonus depreciation for utility property. Accounting principles generally accepted in the United States of America ("GAAP") require the effect on deferred tax assets and liabilities of a change in tax rates be recognized in the period the tax rate change was enacted. As a result of the 2017 Tax Reform, MidAmerican Funding reduced deferred income tax liabilities $1,822 million. As it is probable the change in deferred taxes for the MidAmerican Funding's regulated businesses will be passed back to customers through regulatory mechanisms, MidAmerican Funding increased net regulatory liabilities by $1,845 million.

In December 2017, the Securities and Exchange Commission issued Staff Accounting Bulletin ("SAB") 118 to assist in the implementation process of the 2017 Tax Reform by allowing for calculations to be classified as provisional and subject to remeasurement. There are three different classifications for the accounting: (1) completed, (2) not complete but reasonably estimable or (3) not complete and amounts are not reasonably estimable. MidAmerican Funding has recorded the impacts of 2017 Tax Reform and believes all the impacts to be complete with the exception of interpretations of the bonus depreciation rules. MidAmerican Funding has determined the amounts recorded and the interpretations relating to this item to be provisional and subject to remeasurement during the measurement period upon obtaining the necessary additional information to complete the accounting. MidAmerican Funding believes its interpretations for bonus depreciation to be reasonable; however, as the guidance is clarified estimates may change. The accounting is estimated to be completed by December 2018.

MidAmerican Funding's income tax benefit from continuing operations consists of the following for the years ended December 31 (in millions):

	2017			2016			2015
Current:
Federal	$	(505	)	$	(485	)	$	(418	)
State	(31		)	(16		)	(8		)
	(536		)	(501		)	(426		)
Deferred:
Federal	338			367			282
State	(3		)	(4		)	(5		)
	335			363			277
Investment tax credits	(1		)	(1		)	(1		)
Total	$	(202	)	$	(139	)	$	(150	)

A reconciliation of the federal statutory income tax rate MidAmerican Funding's the effective income tax rate applicable to income before income tax benefit from continuing operations is as follows for the years ended December 31:

	2017		2016		2015
Federal statutory income tax rate	35	%	35	%	35	%
Income tax credits	(77	)	(64	)	(72	)
State income tax, net of federal income tax benefit	(6	)	(3	)	(3	)
Effects of ratemaking	(8	)	(3	)	(12	)
2017 Tax Reform	3		—		—
Other, net	(1	)	—		1
Effective income tax rate	(54	)%	(35	)%	(51	)%

Income tax credits relate primarily to production tax credits earned by MidAmerican Energy's wind-powered generating facilities. Federal renewable electricity production tax credits are earned as energy from qualifying wind-powered generating facilities is produced and sold and are based on a per-kilowatt hour rate pursuant to the applicable federal income tax law. Interim recognition of production tax credits in income is based on the annualized effective tax rate applied each period, similar to all book to tax differences. Recognition of production tax credits in income during interim periods of the year may vary significantly from actual amounts earned. Wind-powered generating facilities are eligible for the credits for 10 years from the date the qualifying generating facilities are placed in service.

MidAmerican Funding's net deferred income tax liability consists of the following as of December 31 (in millions):

	2017			2016
Deferred income tax assets:
Regulatory liabilities	$	443		$	333
Employee benefits	45			66
Asset retirement obligations	160			230
Other	62			82
Total deferred income tax assets	710			711
Deferred income tax liabilities:
Depreciable property	(2,868		)	(3,767		)
Regulatory assets	(42		)	(471		)
Other	(35		)	(41		)
Total deferred income tax liabilities	(2,945		)	(4,279		)
Net deferred income tax liability	$	(2,235	)	$	(3,568	)

As of December 31, 2017, MidAmerican Funding has available $40 million of state tax carryforwards, principally related to $583 million of net operating losses, that expire at various intervals between 2018 and 2036.

The United States Internal Revenue Service has closed its examination of BHE's income tax returns through December 31, 2009, including components related to MidAmerican Funding. In addition, state jurisdictions have closed their examinations of MidAmerican Funding's income tax returns for Iowa through December 31, 2013, for Illinois through December 31, 2008, and for other jurisdictions through December 31, 2009.

A reconciliation of the beginning and ending balances of MidAmerican Funding's net unrecognized tax benefits is as follows for the years ended December 31 (in millions):

	2017			2016
Beginning balance	$	10		$	10
Additions based on tax positions related to the current year	1			—
Additions for tax positions of prior years	23			10
Reductions based on tax positions related to the current year	(4		)	(2		)
Reductions for tax positions of prior years	(19		)	(8		)
Interest and penalties	1			—
Ending balance	$	12		$	10

As of December 31, 2017, MidAmerican Funding had unrecognized tax benefits totaling$39 million that, if recognized, would have an impact on the effective tax rate. The remaining unrecognized tax benefits relate to tax positions for which ultimate deductibility is highly certain but for which there is uncertainty as to the timing of such deductibility. Recognition of these tax benefits, other than applicable interest and penalties, would not affect MidAmerican Funding's effective income tax rate.

Nevada Power Company [Member]

Schedule of Effective Income Tax Rate Reconciliation [Line Items]

Income Taxes [Text Block]

Income Taxes

Tax Cuts and Jobs Act

The 2017 Tax Reform impacts many areas of income tax law. The most material items include the reduction of the federal corporate tax rate from 35% to 21% effective January 1, 2018, limitations on bonus depreciation for utility property and the elimination of the deduction for production activities. GAAP requires the effect on deferred tax assets and liabilities of a change in tax rates be recognized in the period the tax rate change was enacted. As a result of the 2017 Tax Reform, Nevada Power reduced deferred income tax liabilities $787 million. As it is probable the change in deferred taxes will be passed back to customers through regulatory mechanisms, Nevada Power increased net regulatory liabilities by $792 million.

In December 2017, the Securities and Exchange Commission issued Staff Accounting Bulletin ("SAB") 118 to assist in the implementation process of the 2017 Tax Reform by allowing for calculations to be classified as provisional and subject to remeasurement. There are three different classifications for the accounting: (1) completed, (2) not complete but reasonably estimable or (3) not complete and amounts are not reasonably estimable. Nevada Power has recorded the impacts of the 2017 Tax Reform and believes all the impacts to be complete with the exception of the interpretation of the bonus depreciation rules. Nevada Power has determined the amounts recorded and the interpretation relating to this item to be provisional and subject to remeasurement during the measurement period upon obtaining the necessary additional information to complete the accounting. Nevada Power believes its interpretations for bonus depreciation to be reasonable, however, as the guidance is clarified estimates may change. The accounting is estimated to be completed by December 2018.

Income tax expense (benefit) consists of the following for the years ended December 31 (in millions):

	2017			2016			2015
Current – Federal	$	62		$	68		$	—
Deferred – Federal	95			79			163
Investment tax credits	(1		)	(1		)	(1		)
Total income tax expense	$	156		$	146		$	162

A reconciliation of the federal statutory income tax rate to the effective income tax rate applicable to income before income tax expense is as follows for the years ended December 31:

	2017		2016		2015
Federal statutory income tax rate	35	%	35	%	35	%
Effect of ratemaking	1		—		1
Effect of tax rate change	1		—		—
Other	1		(1	)	—
Effective income tax rate	38	%	34	%	36	%

The net deferred income tax liability consists of the following as of December 31 (in millions):

	2017			2016
Deferred income tax assets:
Regulatory liabilities	$	201		$	83
Capital and financial leases	100			170
Employee benefits	18			29
Customer advances	14			23
Federal net operating loss and credit carryforwards	—			5
Other	6			16
Total deferred income tax assets	339			326
Valuation allowance	—			(5		)
Total deferred income tax assets, net	339			321
Deferred income tax liabilities:
Property related items	(796		)	(1,293		)
Regulatory assets	(206		)	(321		)
Capital and financial leases	(97		)	(165		)
Other	(7		)	(16		)
Total deferred income tax liabilities	(1,106		)	(1,795		)
Net deferred income tax liability	$	(767	)	$	(1,474	)

The United States federal jurisdiction is the only significant income tax jurisdiction for NV Energy. In July 2012, the United States Internal Revenue Service and the Joint Committee on Taxation concluded their examination of NV Energy with respect to its United States federal income tax returns for December 31, 2005 through December 31, 2008.

Sierra Pacific Power Company [Member]

Schedule of Effective Income Tax Rate Reconciliation [Line Items]

Income Taxes [Text Block]

Income Taxes

Tax Cuts and Jobs Act

The 2017 Tax Reform impacts many areas of income tax law. The most material items include the reduction of the federal corporate tax rate from 35% to 21% effective January 1, 2018, limitations on bonus depreciation for utility property and the elimination of the deduction for production activities. GAAP requires the effect on deferred tax assets and liabilities of a change in tax rates be recognized in the period the tax rate change was enacted. As a result of the 2017 Tax Reform, Sierra Pacific reduced deferred income tax liabilities $342 million. As it is probable the change in deferred taxes will be passed back to customers through regulatory mechanisms, Sierra Pacific increased net regulatory liabilities by $341 million.

In December 2017, the Securities and Exchange Commission issued Staff Accounting Bulletin ("SAB") 118 to assist in the implementation process of the 2017 Tax Reform by allowing for calculations to be classified as provisional and subject to remeasurement. There are three different classifications for the accounting: (1) completed, (2) not complete but reasonably estimable or (3) not complete and amounts are not reasonably estimable. Sierra Pacific has recorded the impacts of the 2017 Tax Reform and believes all the impacts to be complete with the exception of the interpretation of the bonus depreciation rules. Sierra Pacific has determined the amounts recorded and the interpretation relating to this item to be provisional and subject to remeasurement during the measurement period upon obtaining the necessary additional information to complete the accounting. Sierra Pacific believes its interpretations for bonus depreciation to be reasonable, however, as the guidance is clarified estimates may change. The accounting is estimated to be completed by December 2018.

Income tax expense (benefit) consists of the following for the years ended December 31 (in millions):

	2017			2016			2015
Deferred - Federal	$	56		$	50		$	48
Investment tax credits	(1		)	(1		)	(1		)
Total income tax expense	$	55		$	49		$	47

A reconciliation of the federal statutory income rate to the effective income tax rate applicable to income before income tax expense is as follows for the years ended December 31:

	2017		2016		2015
Federal statutory income tax rate	35	%	35	%	35	%
Effects of ratemaking	—		1		1
Effect of tax rate change	(1	)	—		—
Other	—		1		—
Effective income tax rate	34	%	37	%	36	%

The net deferred income tax liability consists of the following as of December 31 (in millions):

	2017			2016
Deferred income tax assets:
Regulatory liabilities	$	67		$	16
Federal net operating loss and credit carryforwards	10			25
Employee benefit plans	10			22
Capital and financial leases	7			12
Customer Advances	7			9
Commodity derivative contract	—			5
Other	6			6
Total deferred income tax assets	107			95
Deferred income tax liabilities:
Property related items	(349		)	(562		)
Regulatory assets	(74		)	(124		)
Capital and financial leases	(7		)	(12		)
Other	(7		)	(14		)
Total deferred income tax liabilities	(437		)	(712		)
Net deferred income tax liability	$	(330	)	$	(617	)

The following table provides Sierra Pacific's federal net operating loss and tax credit carryforwards and expiration dates as of December 31, 2017 (in millions):

Net operating loss carryforwards	$	18
Deferred income taxes on federal net operating loss carryforwards	$	4
Expiration dates	2033
Other tax credits	$	6
Expiration dates	2021 - 2032

The United States federal jurisdiction is the only significant income tax jurisdiction for NV Energy. In July 2012, the United States Internal Revenue Service and the Joint Committee on Taxation concluded their examination of NV Energy with respect to its United States federal income tax returns for December 31, 2005 through December 31, 2008.