Regulatory Matters (Tables)

12 Months Ended

Dec. 31, 2015

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	2015		2014

Deferred income taxes⁽¹⁾	26 years	$	1,577	$	1,468
Employee benefit plans⁽²⁾	9 years	778		747
Asset disposition costs⁽³⁾	Various	307		329
Deferred net power costs	1 year	140		277
Asset retirement obligations	8 years	281		239
Unrealized loss on regulated derivative contracts	5 years	250		223
Abandoned projects	5 years	136		159
Unamortized contract values	8 years	110		123
Other	Various	706		688
Total regulatory assets		$	4,285	$	4,253

Reflected as:
Current assets		$	130	$	253
Noncurrent assets		4,155		4,000
Total regulatory assets		$	4,285	$	4,253


(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.


(3)	Includes amounts 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. 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	2015		2014

Cost of removal⁽¹⁾	28 years	$	2,167	$	2,215
Deferred net power costs	2 years	206		—
Asset retirement obligations	22 years	147		169
Levelized depreciation	26 years	199		169
Employee benefit plans⁽²⁾	12 years	13		20
Other	Various	301		259
Total regulatory liabilities		$	3,033	$	2,832

Reflected as:
Current liabilities		$	402	$	163
Noncurrent liabilities		2,631		2,669
Total regulatory liabilities		$	3,033	$	2,832


(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	2015		2014

Deferred income taxes⁽¹⁾	26 years	$	437	$	446
Employee benefit plans⁽²⁾	8 years	499		491
Utah mine disposition⁽³⁾	Various	186		194
Unamortized contract values	8 years	110		123
Deferred net power costs	1 year	86		122
Unrealized loss on derivative contracts	5 years	133		85
Other	Various	234		244
Total regulatory assets		$	1,685	$	1,705

Reflected as:
Current assets		$	102	$	131
Noncurrent assets		1,583		1,574
Total regulatory assets		$	1,685	$	1,705


(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	2015		2014

Cost of removal⁽¹⁾	26 years	$	894	$	873
Deferred income taxes	Various	12		13
Other	Various	66		58
Total regulatory liabilities		$	972	$	944

Reflected as:
Current liabilities		$	34	$	34
Noncurrent liabilities		938		910
Total regulatory liabilities		$	972	$	944


(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	2015		2014

Deferred income taxes, net⁽¹⁾	25 years	$	858	$	730
Asset retirement obligations⁽²⁾	6 years	94		62
Employee benefit plans⁽³⁾	11 years	39		42
Unrealized loss on regulated derivative contracts	1 year	20		38
Other	Various	33		36
Total		$	1,044	$	908


(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 11 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	2015		2014

Cost of removal accrual⁽¹⁾	25 years	$	653	$	642
Asset retirement obligations⁽²⁾	22 years	140		159
Other	Various	38		36
Total		$	831	$	837


(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 11for a discussion of asset retirement obligations.

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	2015		2014

Deferred income taxes⁽¹⁾	28 years	$	149	$	156
Merger costs from 1999 merger	28 years	143		149
Decommissioning costs	7 years	121		113
Employee benefit plans⁽²⁾	10 years	98		85
Abandoned projects	4 years	91		107
Deferred operating costs	20 years	87		61
Asset retirement obligations	7 years	79		80
Legacy meters	17 years	64		68
Deferred energy costs	2 years	56		129
Other	Various	169		178
Total regulatory assets		$	1,057	$	1,126

Reflected as:
Current assets		$	—	$	57
Other assets		1,057		1,069
Total regulatory assets		$	1,057	$	1,126


(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	2015		2014

Cost of removal⁽¹⁾	34 years	$	273	$	295
Deferred energy costs	2 years	139		—
Energy efficiency program	1 year	34		25
Other	Various	31		46
Total regulatory liabilities		$	477	$	366

Reflected as:
Current liabilities		$	173	$	40
Other long-term liabilities		304		326
Total regulatory liabilities		$	477	$	366


(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	2015		2014

Employee benefit plans⁽²⁾	10 years	$	126	$	115
Deferred income taxes⁽¹⁾	28 years	90		94
Merger costs from 1999 merger	31 years	83		87
Abandoned projects	9 years	44		51
Deferred energy costs	2 years	—		32
Loss on reacquired debt	17 years	22		24
Other	Various	67		73
Total regulatory assets		$	432	$	476

Reflected as:
Current assets		$	—	$	32
Other assets		432		444
Total regulatory assets		$	432	$	476


(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. 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	2015		2014

Cost of removal⁽¹⁾	40 years	$	208	$	233
Deferred energy costs	2 years	66		—
Renewable energy program	1 year	8		32
Other	Various	26		36
Total regulatory liabilities		$	308	$	301

Reflected as:
Current liabilities		$	78	$	39
Other long-term liabilities		230		262
Total regulatory liabilities		$	308	$	301


(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.