Regulatory Matters (Tables)

12 Months Ended

Dec. 31, 2016

Schedule Of Regulatory Assets and Liabilities [Line Items]

Regulatory assets represent costs that are expected to be recovered in future regulated rates. The Company's regulatory assets reflected on the Consolidated Balance Sheets consist of the following as of December 31 (in millions):



	Weighted
	Average
	Remaining Life	2016		2015

Deferred income taxes⁽¹⁾	27 years	$	1,754	$	1,577
Employee benefit plans⁽²⁾	17 years	816		778
Asset disposition costs	Various	281		307
Deferred net power costs	1 year	38		140
Asset retirement obligations	12 years	301		281
Unrealized loss on regulated derivative contracts	5 years	154		250
Abandoned projects	3 years	159		136
Unamortized contract values	7 years	98		110
Other	Various	856		706
Total regulatory assets		$	4,457	$	4,285

Reflected as:
Current assets		$	150	$	130
Noncurrent assets		4,307		4,155
Total regulatory assets		$	4,457	$	4,285


(1)	Amounts primarily represent income tax benefits related to state accelerated tax depreciation and certain property-related basis differences that were previously flowed through to customers and will be included in regulated rates when the temporary differences reverse.


(2)	Represents amounts not yet recognized as a component of net periodic benefit cost that are expected to be included in regulated rates when recognized.

Regulatory Liabilities [Table Text Block]

Regulatory liabilities represent income to be recognized or amounts to be returned to customers in future periods. The Company's regulatory liabilities reflected on the Consolidated Balance Sheets consist of the following as of December 31 (in millions):



	Weighted
	Average
	Remaining Life	2016		2015

Cost of removal⁽¹⁾	27 years	$	2,242	$	2,167
Deferred net power costs	1 years	64		206
Asset retirement obligations	35 years	122		147
Levelized depreciation	23 years	244		199
Impact fees	6 years	90		—
Employee benefit plans⁽²⁾	12 years	25		13
Unrealized gain on regulated derivative contracts	1 year	6		—
Other	Various	327		301
Total regulatory liabilities		$	3,120	$	3,033

Reflected as:
Current liabilities		$	187	$	402
Noncurrent liabilities		2,933		2,631
Total regulatory liabilities		$	3,120	$	3,033


(1)	Amounts represent estimated costs, as accrued through depreciation rates and exclusive of ARO liabilities, of removing regulated property, plant and equipment in accordance with accepted regulatory practices. Amounts are deducted from rate base or otherwise accrue a carrying cost.


(2)	Represents amounts not yet recognized as a component of net periodic benefit cost that are to be returned to customers in future periods when recognized.

PacifiCorp [Member]

Schedule Of Regulatory Assets and Liabilities [Line Items]

Regulatory Assets [Table Text Block]

Regulatory assets represent costs that are expected to be recovered in future rates. PacifiCorp's regulatory assets reflected on the Consolidated Balance Sheets consist of the following as of December 31 (in millions):



	Weighted
	Average
	Remaining
	Life	2016		2015

Deferred income taxes⁽¹⁾	26 years	$	421	$	437
Employee benefit plans⁽²⁾	21 years	525		499
Utah mine disposition⁽³⁾	Various	166		186
Unamortized contract values	7 years	98		110
Deferred net power costs	1 year	33		86
Unrealized loss on derivative contracts	5 years	73		133
Asset retirement obligation	20 years	82		65
Other	Various	145		169
Total regulatory assets		$	1,543	$	1,685

Reflected as:
Current assets		$	53	$	102
Noncurrent assets		1,490		1,583
Total regulatory assets		$	1,543	$	1,685


(1)	Amounts primarily represent income tax benefits and expense related to certain property-related basis differences and other various items that PacifiCorp is required to pass on to its customers.


(2)	Represents amounts not yet recognized as a component of net periodic benefit cost that are expected to be included in rates when recognized.


(3)	Amounts represent regulatory assets established as a result of the Utah mine disposition discussed below for the net property, plant and equipment not considered probable of disallowance and for the portion of losses associated with the assets held for sale, UMWA 1974 Pension Plan withdrawal and closure costs incurred to date considered probable of recovery.

Regulatory Liabilities [Table Text Block]

Regulatory liabilities represent income to be recognized or amounts to be returned to customers in future periods. PacifiCorp's regulatory liabilities reflected on the Consolidated Balance Sheets consist of the following as of December 31 (in millions):



	Weighted
	Average
	Remaining
	Life	2016		2015

Cost of removal⁽¹⁾	26 years	$	917	$	894
Deferred income taxes	Various	9		12
Other	Various	106		66
Total regulatory liabilities		$	1,032	$	972

Reflected as:
Current liabilities		$	54	$	34
Noncurrent liabilities		978		938
Total regulatory liabilities		$	1,032	$	972


(1)	Amounts represent estimated costs, as accrued through depreciation rates and exclusive of ARO liabilities, of removing property, plant and equipment in accordance with accepted regulatory practices. Amounts are deducted from rate base or otherwise accrue a carrying cost.

MidAmerican Energy Company [Member]

Schedule Of Regulatory Assets and Liabilities [Line Items]

Regulatory Assets [Table Text Block]

Regulatory assets represent costs that are expected to be recovered in future regulated rates. MidAmerican Energy's regulatory assets reflected on the Balance Sheets consist of the following as of December 31 (in millions):



	Average
	Remaining Life	2016		2015

Deferred income taxes, net⁽¹⁾	29 years	$	985	$	858
Asset retirement obligations⁽²⁾	9 years	105		94
Employee benefit plans⁽³⁾	11 years	40		39
Unrealized loss on regulated derivative contracts	1 year	2		20
Other	Various	29		33
Total		$	1,161	$	1,044


(1)	Amounts primarily represent income tax benefits related to state accelerated tax depreciation and certain property-related basis differences that were previously flowed through to customers and will be included in regulated rates when the temporary differences reverse.


(2)	Amount predominantly relates to asset retirement obligations for fossil-fueled and wind-powered generating facilities. Refer to Note 12 for a discussion of asset retirement obligations.


(3)	Represents amounts not yet recognized as a component of net periodic benefit cost that are expected to be included in regulated rates when recognized.

Regulatory Liabilities [Table Text Block]

Regulatory liabilities represent income to be recognized or amounts to be returned to customers in future periods. MidAmerican Energy's regulatory liabilities reflected on the Balance Sheets consist of the following as of December 31 (in millions):



	Average
	Remaining Life	2016		2015

Cost of removal accrual⁽¹⁾	29 years	$	665	$	653
Asset retirement obligations⁽²⁾	36 years	117		140
Pre-funded AFUDC on transmission MVPs⁽³⁾	56 years	35		19
Iowa electric revenue sharing accrual⁽⁴⁾	1 year	30		—
Employee benefit plans⁽⁵⁾	11 years	12		—
Unrealized gain on regulated derivative contracts	1 year	6		—
Other	Various	18		19
Total		$	883	$	831


(1)	Amounts represent estimated costs, as accrued through depreciation rates and exclusive of ARO liabilities, of removing utility plant in accordance with accepted regulatory practices. Amounts are deducted from rate base or otherwise accrue a carrying cost.


(2)	Amount predominantly represents the excess of nuclear decommission trust assets over the related asset retirement obligation. Refer to Note 12 for a discussion of asset retirement obligations.


(3)	Represents AFUDC accrued on transmission MVPs that is deducted from rate base as a result of the inclusion of related construction work-in-progress in rate base.


(4)	Represents current-year accruals under a regulatory arrangement in Iowa in which equity returns exceeding specified thresholds reduce utility plant upon final determination.


(5)	Represents amounts not yet recognized as a component of net periodic benefit cost that are to be returned to customers in future periods when recognized.

Nevada Power Company [Member]

Schedule Of Regulatory Assets and Liabilities [Line Items]

Regulatory Assets [Table Text Block]

Regulatory assets represent costs that are expected to be recovered in future rates. Nevada Power's regulatory assets reflected on the Consolidated Balance Sheets consist of the following as of December 31 (in millions):



	Weighted
	Average
	Remaining Life	2016		2015

Deferred income taxes⁽¹⁾	27 years	$	141	$	149
Merger costs from 1999 merger	28 years	136		143
Deferred operating costs	20 years	127		87
Decommissioning costs	7 years	114		121
Employee benefit plans⁽²⁾	10 years	105		98
Abandoned projects	3 years	75		91
Asset retirement obligations	7 years	74		79
Legacy meters	16 years	60		64
Merrill Lynch deferred energy costs	3 years	40		56
Other	Various	148		169
Total regulatory assets		$	1,020	$	1,057

Reflected as:
Current assets		$	20	$	—
Other assets		1,000		1,057
Total regulatory assets		$	1,020	$	1,057


(1)	Amounts represent income tax benefits related to accelerated tax depreciation and certain property-related basis differences that were previously flowed through to customers and will be included in regulated rates when the temporary differences reverse.


(2)	Represents amounts not yet recognized as a component of net periodic benefit cost that are expected to be included in regulated rates when recognized.

Regulatory Liabilities [Table Text Block]

Regulatory liabilities represent income to be recognized or amounts to be returned to customers in future periods. Nevada Power's regulatory liabilities reflected on the Consolidated Balance Sheets consist of the following as of December 31 (in millions):



	Weighted
	Average
	Remaining Life	2016		2015

Cost of removal⁽¹⁾	33 years	$	294	$	273
Impact fees	6 years	90		—
Energy efficiency program	1 year	37		34
Deferred energy costs	1 year	—		139
Other	Various	32		31
Total regulatory liabilities		$	453	$	477

Reflected as:
Current liabilities		$	37	$	173
Other long-term liabilities		416		304
Total regulatory liabilities		$	453	$	477


(1)	Amounts represent estimated costs, as accrued through depreciation rates and exclusive of ARO liabilities, of removing regulated property, plant and equipment in accordance with accepted regulatory practices. Amounts are deducted from rate base or otherwise accrue a carrying cost.

Sierra Pacific Power Company [Member]

Schedule Of Regulatory Assets and Liabilities [Line Items]

Regulatory Assets [Table Text Block]

Regulatory assets represent costs that are expected to be recovered in future rates. Sierra Pacific's regulatory assets reflected on the Consolidated Balance Sheets consist of the following as of December 31 (in millions):



	Weighted
	Average
	Remaining Life	2016		2015

Employee benefit plans⁽¹⁾	10 years	$	128	$	126
Deferred income taxes⁽²⁾	27 years	85		90
Merger costs from 1999 merger	30 years	80		83
Abandoned projects	9 years	39		44
Renewable energy programs	1 year	25		—
Losses on reacquired debt	17 years	22		22
Other	Various	56		67
Total regulatory assets		$	435	$	432

Reflected as:
Current assets		$	25	$	—
Other assets		410		432
Total regulatory assets		$	435	$	432


(1)	Represents amounts not yet recognized as a component of net periodic benefit cost that are expected to be included in regulated rates when recognized.


(2)	Amounts represent income tax benefits related to accelerated tax depreciation and certain property-related basis differences that were previously flowed through to customers and will be included in regulated rates when the temporary differences reverse.

Regulatory Liabilities [Table Text Block]

Regulatory liabilities represent income to be recognized or amounts to be returned to customers in future periods. Sierra Pacific's regulatory liabilities reflected on the Consolidated Balance Sheets consist of the following as of December 31 (in millions):



	Weighted
	Average
	Remaining Life	2016		2015

Cost of removal⁽¹⁾	39 years	$	205	$	208
Deferred energy costs	1 year	64		66
Renewable energy program	1 year	—		8
Other	Various	21		26
Total regulatory liabilities		$	290	$	308

Reflected as:
Current liabilities		$	69	$	78
Other long-term liabilities		221		230
Total regulatory liabilities		$	290	$	308


(1)	Amounts represent estimated costs, as accrued through depreciation rates and exclusive of ARO liabilities, of removing regulated property, plant and equipment in accordance with accepted regulatory practices. Amounts are deducted from rate base or otherwise accrue a carrying cost.