Income Taxes (Tables)

12 Months Ended

Dec. 31, 2017

Schedule of Effective Income Tax Rate Reconciliation [Line Items]

Components of Income Tax Expense (Benefit) [Table Text Block]

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

Effective Income Tax Rate Reconciliation [Table Text Block]

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	%

Components of Net Deferred Income Tax Liability [Table Text Block]

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	)

Summary of Operating Loss Carryforwards [Table Text Block]

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.

Net Unrecognized Tax Benefits Roll Forward [Table Text Block]

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

PacifiCorp [Member]

Schedule of Effective Income Tax Rate Reconciliation [Line Items]

Components of Income Tax Expense (Benefit) [Table Text Block]

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

Effective Income Tax Rate Reconciliation [Table Text Block]

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	%

Components of Net Deferred Income Tax Liability [Table Text Block]

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	)

Summary of Operating Loss Carryforwards [Table Text Block]

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

MidAmerican Energy Company [Member]

Schedule of Effective Income Tax Rate Reconciliation [Line Items]

Components of Income Tax Expense (Benefit) [Table Text Block]

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	)

Effective Income Tax Rate Reconciliation [Table Text Block]

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	)%

Components of Net Deferred Income Tax Liability [Table Text Block]

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	)

Net Unrecognized Tax Benefits Roll Forward [Table Text Block]

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

MidAmerican Funding, LLC and Subsidiaries [Domain]

Schedule of Effective Income Tax Rate Reconciliation [Line Items]

Components of Income Tax Expense (Benefit) [Table Text Block]

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	)

Effective Income Tax Rate Reconciliation [Table Text Block]

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	)%

Components of Net Deferred Income Tax Liability [Table Text Block]

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	)

Net Unrecognized Tax Benefits Roll Forward [Table Text Block]

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

Nevada Power Company [Member]

Schedule of Effective Income Tax Rate Reconciliation [Line Items]

Components of Income Tax Expense (Benefit) [Table Text Block]

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

Effective Income Tax Rate Reconciliation [Table Text Block]

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	%

Components of Net Deferred Income Tax Liability [Table Text Block]

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	)

Sierra Pacific Power Company [Member]

Schedule of Effective Income Tax Rate Reconciliation [Line Items]

Components of Income Tax Expense (Benefit) [Table Text Block]

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

Effective Income Tax Rate Reconciliation [Table Text Block]

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	%

Components of Net Deferred Income Tax Liability [Table Text Block]

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	)

Summary of Operating Loss Carryforwards [Table Text Block]

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