Employee Benefit Plans (Tables)

12 Months Ended

Dec. 31, 2019

Defined Benefit Plan Disclosure [Line Items]

Schedule of Net Benefit Costs [Table Text Block]

Net periodic benefit cost for the plans included the following components for the years ended December 31 (in millions):

	Pension									Other Postretirement
	2019			2018			2017			2019			2018			2017
Service cost	$	16		$	21		$	24		$	8		$	9		$	9
Interest cost	111			105			116			27			24			29
Expected return on plan assets	(154		)	(164		)	(160		)	(40		)	(41		)	(40		)
Settlement	—			21			—			—			—			—
Net amortization	31			28			25			(6		)	(13		)	(14		)
Net periodic benefit cost (credit)	$	4		$	11		$	5		$	(11	)	$	(21	)	$	(16	)

Net periodic benefit cost for the UK Plan included the following components for the years ended December 31 (in millions):

	2019			2018			2017
Service cost	$	16		$	19		$	23
Interest cost	49			56			58
Expected return on plan assets	(100		)	(101		)	(100		)
Settlement	26			44			31
Net amortization	46			45			63
Net periodic benefit cost	$	37		$	63		$	75

Changes in Fair Value of Plan Assets [Table Text Block]

The following table is a reconciliation of the fair value of plan assets for the years ended December 31 (in millions):

	Pension						Other Postretirement
	2019			2018			2019			2018
Plan assets at fair value, beginning of year	$	2,396		$	2,761		$	664		$	736
Employer contributions	12			38			2			8
Participant contributions	—			—			9			8
Actual return on plan assets	456			(147		)	122			(38		)
Settlement	(22		)	(119		)	—			—
Benefits paid	(186		)	(137		)	(55		)	(50		)
Plan assets at fair value, end of year	$	2,656		$	2,396		$	742		$	664

The following table is a reconciliation of the fair value of plan assets for the years ended December 31 (in millions):

	2019			2018
Plan assets at fair value, beginning of year	$	1,989		$	2,368
Employer contributions	56			60
Participant contributions	1			1
Actual return on plan assets	194			(44		)
Settlement	(99		)	(205		)
Benefits paid	(71		)	(71		)
Foreign currency exchange rate changes	81			(120		)
Plan assets at fair value, end of year	$	2,151		$	1,989

Changes in Projected Benefit Obligations [Table Text Block]

following table is a reconciliation of the benefit obligation for the years ended December 31 (in millions):

	2019			2018
Benefit obligation, beginning of year	$	1,833		$	2,201
Service cost	16			19
Interest cost	49			56
Participant contributions	1			1
Actuarial loss (gain)	175			(87		)
Settlement	(99		)	(182		)
Amendment	—			8
Benefits paid	(71		)	(71		)
Foreign currency exchange rate changes	115			(112		)
Benefit obligation, end of year	$	2,019		$	1,833
Accumulated benefit obligation, end of year	$	1,786		$	1,637

The following table is a reconciliation of the benefit obligations for the years ended December 31 (in millions):

	Pension						Other Postretirement
	2019			2018			2019			2018
Benefit obligation, beginning of year	$	2,718		$	3,006		$	672		$	721
Service cost	16			21			8			9
Interest cost	111			105			27			24
Participant contributions	—			—			9			8
Actuarial loss (gain)	242			(160		)	12			(40		)
Amendment	(1		)	2			—			—
Settlement	(22		)	(119		)	—			—
Benefits paid	(186		)	(137		)	(55		)	(50		)
Benefit obligation, end of year	$	2,878		$	2,718		$	673		$	672
Accumulated benefit obligation, end of year	$	2,867		$	2,709

Benefit Obligations in Excess of Fair Value of Plan Assets [Table Text Block]

The funded status of the plans and the amounts recognized on the Consolidated Balance Sheets as of December 31 are as follows (in millions):

	Pension						Other Postretirement
	2019			2018			2019			2018
Plan assets at fair value, end of year	$	2,656		$	2,396		$	742		$	664
Benefit obligation, end of year	2,878			2,718			673			672
Funded status	$	(222	)	$	(322	)	$	69		$	(8	)
Amounts recognized on the Consolidated Balance Sheets:
Other assets	$	73		$	20		$	76		$	5
Other current liabilities	(13		)	(13		)	—			—
Other long-term liabilities	(282		)	(329		)	(7		)	(13		)
Amounts recognized	$	(222	)	$	(322	)	$	69		$	(8	)

The funded status of the UK Plan and the amounts recognized on the Consolidated Balance Sheets as of December 31 are as follows (in millions):

	2019		2018
Plan assets at fair value, end of year	$	2,151	$	1,989
Benefit obligation, end of year	2,019		1,833
Funded status	$	132	$	156
Amounts recognized on the Consolidated Balance Sheets:
Other assets	$	132	$	156

The fair value of plan assets, projected benefit obligation and accumulated benefit obligation for (1) pension and other postretirement benefit plans with a projected benefit obligation in excess of the fair value of plan assets and (2) pension plans with an accumulated benefit obligation in excess of the fair value of plan assets as of December 31 are as follows (in millions):

	Pension				Other Postretirement
	2019		2018		2019		2018
Fair value of plan assets	$	1,939	$	1,752	$	439	$	417
Projected benefit obligation	$	2,227	$	2,091	$	446	$	429
Accumulated benefit obligation	$	2,222	$	2,085

Net Periodic Benefit Costs Not Yet Recognized [Table Text Block]

A reconciliation of the amounts not yet recognized as components of net periodic benefit cost for the years ended December 31, 2019 and 2018 is as follows (in millions):

							Accumulated
							Other
	Regulatory			Regulatory			Comprehensive
	Asset			Liability			Loss			Total
Pension
Balance, December 31, 2017	$	665		$	(43	)	$	20		$	642
Net loss (gain) arising during the year	114			43			(6		)	151
Net prior service cost arising during the year	—			—			2			2
Settlement	(21		)	—			—			(21		)
Net amortization	(28		)	—			—			(28		)
Total	65			43			(4		)	104
Balance, December 31, 2018	730			—			16			746
Net (gain) loss arising during the year	(38		)	(33		)	10			(61		)
Net prior service credit arising during the year	—			—			(2		)	(2		)
Net amortization	(31		)	—			—			(31		)
Total	(69		)	(33		)	8			(94		)
Balance, December 31, 2019	$	661		$	(33	)	$	24		$	652

							Accumulated
							Other
	Regulatory			Regulatory			Comprehensive
	Asset			Liability			Loss			Total
Other Postretirement
Balance, December 31, 2017	$	10		$	(26	)	$	—		$	(16	)
Net loss arising during the year	23			14			1			38
Net amortization	11			2			—			13
Total	34			16			1			51
Balance, December 31, 2018	44			(10		)	1			35
Net gain arising during the year	(45		)	(23		)	(4		)	(72		)
Net amortization	5			1			—			6
Total	(40		)	(22		)	(4		)	(66		)
Balance, December 31, 2019	$	4		$	(32	)	$	(3	)	$	(31	)

A reconciliation of the amounts not yet recognized as components of net periodic benefit cost, which are included in accumulated other comprehensive loss on the Consolidated Balance Sheets, for the years ended December 31 is as follows (in millions):

	2019			2018
Balance, beginning of year	$	480		$	510
Net loss arising during the year	81			59
Net prior service cost arising during the year	—			8
Settlement	(26		)	(22		)
Net amortization	(46		)	(45		)
Foreign currency exchange rate changes	60			(30		)
Total	69			(30		)
Balance, end of year	$	549		$	480

The portion of the funded status of the plans not yet recognized in net periodic benefit cost as of December 31 is as follows (in millions):

	Pension						Other Postretirement
	2019			2018			2019			2018
Net loss	$	653		$	747		$	(23	)	$	50
Prior service credit	(2		)	—			(14		)	(22		)
Regulatory deferrals	1			(1		)	6			7
Total	$	652		$	746		$	(31	)	$	35

The portion of the funded status of the UK Plan not yet recognized in net periodic benefit cost as of December 31 is as follows (in millions):

	2019		2018
Net loss	$	543	$	472
Prior service cost	6		8
Total	$	549	$	480

Defined Benefit Plans, Amounts To Be Recognized In Following Year [Table Text Block]

Plan Assumptions [Table Text Block]

Assumptions used to determine benefit obligations and net periodic benefit cost were as follows:

	2019		2018		2017
Benefit obligations as of December 31:
Discount rate	2.10	%	2.90	%	2.60	%
Rate of compensation increase	3.30	%	3.55	%	3.45	%
Rate of future price inflation	2.80	%	3.05	%	2.95	%
Net periodic benefit cost for the years ended December 31:
Discount rate	2.90	%	2.60	%	2.70	%
Expected return on plan assets	5.10	%	4.90	%	5.00	%
Rate of compensation increase	3.55	%	3.45	%	3.00	%
Rate of future price inflation	3.05	%	2.95	%	3.00	%

Weighted-average assumptions used to determine benefit obligations and net periodic benefit cost were as follows:

	Pension						Other Postretirement
	2019		2018		2017		2019		2018		2017
Benefit obligations as of December 31:
Discount rate	3.32	%	4.25	%	3.60	%	3.24	%	4.21	%	3.57	%
Rate of compensation increase	2.75	%	2.75	%	2.75	%	NA		NA		NA
Interest crediting rates for cash balance plan
2017	NA		NA		2.49	%	NA		NA		NA
2018	NA		3.38	%	3.06	%	NA		NA		NA
2019	3.22	%	3.54	%	3.06	%	NA		NA		NA
2020	2.94	%	3.54	%	2.72	%	NA		NA		NA
2021	2.94	%	3.56	%	2.72	%	NA		NA		NA
2022	3.02	%	3.56	%	2.72	%	NA		NA		NA
Net periodic benefit cost for the years ended December 31:
Discount rate	4.25	%	3.60	%	4.06	%	4.21	%	3.57	%	4.01	%
Expected return on plan assets	6.48	%	6.36	%	6.55	%	6.39	%	6.44	%	6.73	%
Rate of compensation increase	2.75	%	2.75	%	2.75	%	NA		NA		NA
Interest crediting rate for cash balance plan	3.22	%	3.38	%	2.49	%	NA		NA		NA

In establishing its assumption as to the expected return on plan assets, the Company utilizes the asset allocation and return assumptions for each asset class based on historical performance and forward-looking views of the financial markets.

	2019		2018
Assumed healthcare cost trend rates as of December 31:
Healthcare cost trend rate assumed for next year	6.50	%	6.80	%
Rate that the cost trend rate gradually declines to	5.00	%	5.00	%
Year that the rate reaches the rate it is assumed to remain at	2025		2025

Effect of One-Percentage-Point Change in Assumed Health Care Cost Trend Rates [Table Text Block]

Expected Benefit Payments [Table Text Block]

Employer contributions to the UK Plan are expected to be £43 million during 2020. The expected benefit payments to participants in the UK Plan for 2020 through 2024 and for the five years thereafter excluding lump sum settlement elections, using the foreign currency exchange rate as of December 31, 2019, are summarized below (in millions):

2020	$	74
2021	75
2022	77
2023	79
2024	81
2025-2029	436

The expected benefit payments to participants in the Company's pension and other postretirement benefit plans for 2020 through 2024 and for the five years thereafter are summarized below (in millions):

	Projected Benefit
	Payments
			Other
	Pension		Postretirement
2020	$	233	$	57
2021	218		56
2022	213		55
2023	212		54
2024	205		51
2025-2029	927		224

Allocation of Plan Assets [Table Text Block]

The target allocations (percentage of plan assets) for the UK Plan assets are as follows as of December 31, 2019:

	%
Debt securities(1)	50-55
Equity securities(1)	35-40
Real estate funds and other	5-15

(1) For purposes of target allocation percentages and consistent with the plans' investment policy, investment funds have been allocated based on the underlying investments in debt and equity securities.

The target allocations (percentage of plan assets) for the Company's pension and other postretirement benefit plan assets are as follows as of December 31, 2019:

		Other
	Pension	Postretirement
	%	%
PacifiCorp:
Debt securities(1)	30-43	33-37
Equity securities(1)	48-65	62-66
Limited partnership interests	6-12	1-3
MidAmerican Energy:
Debt securities(1)	20-50	25-45
Equity securities(1)	60-80	45-80
Real estate funds	2-8	—
Other	0-3	0-5
NV Energy:
Debt securities(1)	53-77	40
Equity securities(1)	23-47	60

(1) For purposes of target allocation percentages and consistent with the plans' investment policy, investment funds are allocated based on the underlying investments in debt and equity securities.

Fair Value, Assets and Liabilities Measured on Recurring Basis [Table Text Block]

The following table presents the fair value of the UK Plan assets, by major category (in millions):

	Input Levels for Fair Value Measurements(1)
	Level 1		Level 2		Level 3		Total
As of December 31, 2019:
Cash equivalents	$	3	$	24	$	—	$	27
Debt securities:
United Kingdom government obligations	960		—		—		960
Equity securities:
Investment funds(2)	—		818		—		818
Real estate funds	—		—		243		243
Total	$	963	$	842	$	243	2,048
Investment funds(2) measured at net asset value							103
Total assets measured at fair value							$	2,151
As of December 31, 2018:
Cash equivalents	$	3	$	59	$	—	$	62
Debt securities:
United Kingdom government obligations	891		—		—		891
Equity securities:
Investment funds(2)	—		697		—		697
Real estate funds	—		—		239		239
Total	$	894	$	756	$	239	1,889
Investment funds(2) measured at net asset value							100
Total assets measured at fair value							$	1,989

(1) Refer to Note 15 for additional discussion regarding the three levels of the fair value hierarchy.

(2) Investment funds are comprised of mutual funds and collective trust funds. These funds consist of equity and debt securities of approximately 38% and 62%, respectively, for 2019 and 36% and 64%, respectively, for 2018.

The following table presents the fair value of plan assets, by major category, for the Company's defined benefit pension plans (in millions):

	Input Levels for Fair Value Measurements(1)
	Level 1		Level 2		Total
As of December 31, 2019:
Cash equivalents	$	27	$	36	$	63
Debt securities:
United States government obligations	210		—		210
International government obligations	—		5		5
Corporate obligations	—		376		376
Municipal obligations	—		28		28
Agency, asset and mortgage-backed obligations	—		115		115
Equity securities:
United States companies	547		1		548
International companies	136		—		136
Investment funds(2)	125		—		125
Total assets in the fair value hierarchy	$	1,045	$	561	1,606
Investment funds(2) measured at net asset value					915
Limited partnership interests(3) measured at net asset value					93
Real estate funds measured at net asset value					42
Total assets measured at fair value					$	2,656
As of December 31, 2018:
Cash equivalents	$	8	$	41	$	49
Debt securities:
United States government obligations	160		—		160
International government obligations	—		5		5
Corporate obligations	—		373		373
Municipal obligations	—		29		29
Agency, asset and mortgage-backed obligations	—		123		123
Equity securities:
United States companies	492		1		493
International companies	108		—		108
Investment funds(2)	119		—		119
Total assets in the fair value hierarchy	$	887	$	572	1,459
Investment funds(2) measured at net asset value					792
Limited partnership interests(3) measured at net asset value					104
Real estate funds measured at net asset value					41
Total assets measured at fair value					$	2,396

(1) Refer to Note 15 for additional discussion regarding the three levels of the fair value hierarchy.

(2) Investment funds are comprised of mutual funds and collective trust funds. These funds consist of equity and debt securities of approximately 62% and 38%, respectively, for 2019 and 59% and 41%, respectively, for 2018. Additionally, these funds are invested in United States and international securities of approximately 66% and 34%, respectively, for 2019 and 73% and 27%, respectively, for 2018.

(3) Limited partnership interests include several funds that invest primarily in real estate, buyout, growth equity and venture capital.

The following table presents the fair value of plan assets, by major category, for the Company's defined benefit other postretirement plans (in millions):

	Input Levels for Fair Value Measurements(1)
	Level 1		Level 2		Total
As of December 31, 2019:
Cash equivalents	$	17	$	1	$	18
Debt securities:
United States government obligations	23		—		23
Corporate obligations	—		44		44
Municipal obligations	—		57		57
Agency, asset and mortgage-backed obligations	—		33		33
Equity securities:
United States companies	151		—		151
International companies	6		—		6
Investment funds	236		—		236
Total assets in the fair value hierarchy	$	433	$	135	568
Investment funds measured at net asset value					169
Limited partnership interests measured at net asset value					5
Total assets measured at fair value					$	742
As of December 31, 2018:
Cash equivalents	$	10	$	2	$	12
Debt securities:
United States government obligations	13		—		13
Corporate obligations	—		42		42
Municipal obligations	—		45		45
Agency, asset and mortgage-backed obligations	—		30		30
Equity securities:
United States companies	158		—		158
International companies	6		—		6
Investment funds(2)	202		1		203
Total assets in the fair value hierarchy	$	389	$	120	509
Investment funds(2) measured at net asset value					149
Limited partnership interests(3) measured at net asset value					6
Total assets measured at fair value					$	664

(1) Refer to Note 15 for additional discussion regarding the three levels of the fair value hierarchy.

(2) Investment funds are comprised of mutual funds and collective trust funds. These funds consist of equity and debt securities of approximately 58% and 42%, respectively, for 2019 and 65% and 35%, respectively, for 2018. Additionally, these funds are invested in United States and international securities of approximately 75% and 25%, respectively, for 2019 and 79% and 21%, respectively, for 2018.

(3) Limited partnership interests include several funds that invest primarily in real estate, buyout, growth equity and venture capital.

The following table presents the Company's assets and liabilities recognized on the Consolidated Balance Sheets and measured at fair value on a recurring basis (in millions):

	Input Levels for Fair Value Measurements
	Level 1			Level 2			Level 3			Other(1)			Total
As of December 31, 2019:
Assets:
Commodity derivatives	$	—		$	45		$	108		$	(24	)	$	129
Interest rate derivatives	—			2			14			—			16
Mortgage loans held for sale	—			1,039			—			—			1,039
Money market mutual funds(2)	824			—			—			—			824
Debt securities:
United States government obligations	189			—			—			—			189
International government obligations	—			4			—			—			4
Corporate obligations	—			58			—			—			58
Municipal obligations	—			1			—			—			1
Agency, asset and mortgage-backed obligations	—			1			—			—			1
Equity securities:
United States companies	336			—			—			—			336
International companies	1,131			—			—			—			1,131
Investment funds	169			—			—			—			169
	$	2,649		$	1,150		$	122		$	(24	)	$	3,897
Liabilities:
Commodity derivatives	$	(4	)	$	(143	)	$	(11	)	$	103		$	(55	)
Interest rate derivatives	(2		)	(19		)	—			—			(21		)
	$	(6	)	$	(162	)	$	(11	)	$	103		$	(76	)

As of December 31, 2018:
Assets:
Commodity derivatives	$	1		$	91		$	108		$	(52	)	$	148
Interest rate derivatives	1			13			10			—			24
Mortgage loans held for sale	—			468			—			—			468
Money market mutual funds(2)	409			—			—			—			409
Debt securities:
United States government obligations	187			—			—			—			187
International government obligations	—			4			—			—			4
Corporate obligations	—			46			—			—			46
Municipal obligations	—			2			—			—			2
Agency, asset and mortgage-backed obligations	—			1			—			—			1
Equity securities:
United States companies	256			—			—			—			256
International companies	1,441			—			—			—			1,441
Investment funds	128			—			—			—			128
	$	2,423		$	625		$	118		$	(52	)	$	3,114
Liabilities:
Commodity derivatives	$	(1	)	$	(180	)	$	(9	)	$	111		$	(79	)
Interest rate derivatives	—			(32		)	—			—			(32		)
	$	(1	)	$	(212	)	$	(9	)	$	111		$	(111	)

(1) Represents netting under master netting arrangements and a net cash collateral receivable of $79 million and $59 million as of December 31, 2019 and 2018, respectively.

(2) Amounts are included in cash and cash equivalents; other current assets; and noncurrent investments and restricted cash and investments on the Consolidated Balance Sheets. The fair value of these money market mutual funds approximates cost.

Level Three Defined Benefit Plan Assets Roll Forward [Table Text Block]

The following table reconciles the beginning and ending balances of the UK Plan assets measured at fair valueusing significant Level 3 inputs for the years ended December 31 (in millions):

	Real Estate Funds
	2019			2018			2017
Beginning balance	$	239		$	230		$	105
Actual return on plan assets still held at period end	(5		)	23			6
Purchases	—			—			104
Foreign currency exchange rate changes	9			(14		)	15
Ending balance	$	243		$	239		$	230

PacifiCorp [Member]

Defined Benefit Plan Disclosure [Line Items]

Schedule of Net Benefit Costs [Table Text Block]

Net periodic benefit cost for the plans included the following components for the years ended December 31 (in millions):

	Pension									Other Postretirement
	2019			2018			2017			2019			2018			2017
Service cost	$	—		$	—		$	—		$	2		$	2		$	2
Interest cost	44			43			49			12			11			14
Expected return on plan assets	(67		)	(72		)	(72		)	(21		)	(21		)	(21		)
Settlement	—			22			—			—			—			—
Net amortization	11			13			14			—			(6		)	(6		)
Net periodic benefit (credit) cost	$	(12	)	$	6		$	(9	)	$	(7	)	$	(14	)	$	(11	)

Changes in Fair Value of Plan Assets [Table Text Block]

The following table is a reconciliation of the fair value of plan assets for the years ended December 31 (in millions):

	Pension						Other Postretirement
	2019			2018			2019			2018
Plan assets at fair value, beginning of year	$	942		$	1,111		$	297		$	332
Employer contributions	4			4			1			1
Participant contributions	—			—			5			5
Actual return on plan assets	181			(52		)	55			(16		)
Settlement	—			(52		)	—			—
Benefits paid	(91		)	(69		)	(24		)	(25		)
Plan assets at fair value, end of year	$	1,036		$	942		$	334		$	297

Changes in Projected Benefit Obligations [Table Text Block]

The following table is a reconciliation of the benefit obligations for the years ended December 31 (in millions):

	Pension						Other Postretirement
	2019			2018			2019			2018
Benefit obligation, beginning of year	$	1,105		$	1,251		$	298		$	331
Service cost	—			—			2			2
Interest cost	44			43			12			11
Participant contributions	—			—			5			5
Actuarial loss (gain)	109			(68		)	11			(26		)
Settlement	—			(52		)	—			—
Benefits paid	(91		)	(69		)	(24		)	(25		)
Benefit obligation, end of year	$	1,167		$	1,105		$	304		$	298
Accumulated benefit obligation, end of year	$	1,167		$	1,105

Benefit Obligations in Excess of Fair Value of Plan Assets [Table Text Block]

The funded status of the plans and the amounts recognized on the Consolidated Balance Sheets as of December 31 are as follows (in millions):

	Pension						Other Postretirement
	2019			2018			2019		2018
Plan assets at fair value, end of year	$	1,036		$	942		$	334	$	297
Less - Benefit obligation, end of year	1,167			1,105			304		298
Funded status	$	(131	)	$	(163	)	$	30	$	(1	)
Amounts recognized on the Consolidated Balance Sheets:
Other assets	$	7		$	3		$	30	$	—
Other current liabilities	(4		)	(4		)	—		—
Other long-term liabilities	(134		)	(162		)	—		(1		)
Amounts recognized	$	(131	)	$	(163	)	$	30	$	(1	)

Net Periodic Benefit Costs Not Yet Recognized [Table Text Block]

The portion of the funded status of the plans not yet recognized in net periodic benefit cost as of December 31 is as follows (in millions):

	Pension					Other Postretirement
	2019		2018			2019			2018
Net loss (gain)	$	442	$	461		$	(26	)	$	(2	)
Regulatory deferrals	1		(1		)	6			7
Total	$	443	$	460		$	(20	)	$	5

A reconciliation of the amounts not yet recognized as components of net periodic benefit cost for the years ended December 31, 2019 and 2018 is as follows (in millions):

				Accumulated
				Other
	Regulatory			Comprehensive
	Asset			Loss			Total
Pension
Balance, December 31, 2017	$	418		$	20		$	438
Net loss (gain) arising during the year	59			(2		)	57
Net amortization	(12		)	(1		)	(13		)
Settlement	(22		)	—			(22		)
Total	25			(3		)	22
Balance, December 31, 2018	443			17			460
Net (gain) loss arising during the year	(11		)	5			(6		)
Net amortization	(10		)	(1		)	(11		)
Total	(21		)	4			(17		)
Balance, December 31, 2019	$	422		$	21		$	443

	Regulatory
	Asset (Liability)
Other Postretirement
Balance, December 31, 2017	$	(11	)
Net loss arising during the year	10
Net amortization	6
Total	16
Balance, December 31, 2018	5
Net gain arising during the year	(25		)
Net amortization	—
Total	(25		)
Balance, December 31, 2019	$	(20	)

Defined Benefit Plans, Amounts To Be Recognized In Following Year [Table Text Block]

Plan Assumptions [Table Text Block]

ssumptions used to determine benefit obligations and net periodic benefit cost were as follows:

	Pension						Other Postretirement
	2019		2018		2017		2019		2018		2017
Benefit obligations as of December 31:
Discount rate	3.25	%	4.25	%	3.60	%	3.20	%	4.25	%	3.60	%
Rate of compensation increase	N/A		N/A		N/A		N/A		N/A		N/A
Interest crediting rates for cash balance plan (1)(2)(3)	2.27	%	3.40	%	1.61	%	N/A		N/A		N/A
Net periodic benefit cost for the years ended December 31:
Discount rate	4.25	%	3.60	%	4.05	%	4.25	%	3.60	%	4.05	%
Expected return on plan assets	7.00		7.00		7.25		6.86		6.86		7.25
Rate of compensation increase	N/A		N/A		N/A		N/A		N/A		N/A

(1) 2019 Cash Balance Interest Crediting Rate assumption is 2.27% for 2020-2021 and 2.10% for 2022 and all future years for nonunion participants and 2.16% for 2020-2021 and 2.70% for 2022+ for union participants.

(2) 2018 Cash Balance Interest Crediting Rate assumption was 3.40% for 2019 and all future years for nonunion participants and 3.15% for 2019-2020 and 3.25% for 2021+ for union participants.

(3) 2017 Cash Balance Interest Crediting Rate assumption was 2.26% for 2018-2019 and 1.60% for 2020+ for nonunion participants and 2.78% for 2018-2019 and 2.60% for 2020+ for union participants.

In establishing its assumption as to the expected return on plan assets, PacifiCorp utilizes the asset allocation and return assumptions for each asset class based on historical performance and forward-looking views of the financial markets.

As a result of a plan amendment effective on January 1, 2017, the benefit obligation for the Retirement Plan is no longer affected by future increases in compensation. As a result of a labor settlement reached with UMWA in December 2014, the benefit obligation for the other postretirement plan is no longer affected by healthcare cost trends.

Expected Benefit Payments [Table Text Block]

The expected benefit payments to participants in PacifiCorp's pension and other postretirement benefit plans for 2020 through 2024 and for the five years thereafter are summarized below (in millions):

	Projected Benefit Payments
	Pension		Other Postretirement
2020	$	112	$	27
2021	98		24
2022	94		23
2023	89		23
2024	83		21
2025-2029	350		94

Allocation of Plan Assets [Table Text Block]

The target allocations (percentage of plan assets) for PacifiCorp's pension and other postretirement benefit plan assets are as follows as of December 31, 2019:

	Pension(1)	Other Postretirement(1)
	%	%
Debt securities(2)	30 - 43	33 - 37
Equity securities(2)	48 - 65	62 - 66
Limited partnership interests	6 - 12	1 - 3

(1) PacifiCorp's Retirement Plan trust includes a separate account that is used to fund benefits for the other postretirement benefit plan. In addition to this separate account, the assets for the other postretirement benefit plan are held in Voluntary Employees' Beneficiary Association ("VEBA") trusts, each of which has its own investment allocation strategies. Target allocations for the other postretirement benefit plan include the separate account of the Retirement Plan trust and the VEBA trusts.

(2) For purposes of target allocation percentages and consistent with the plans' investment policy, investment funds are allocated based on the underlying investments in debt and equity securities.

Fair Value, Assets and Liabilities Measured on Recurring Basis [Table Text Block]

The following table presents the fair value of plan assets, by major category, for PacifiCorp's defined benefit pension plan (in millions):

	Input Levels for Fair Value Measurements
	Level 1(1)		Level 2(1)		Level 3(1)		Total
As of December 31, 2019:
Cash equivalents	$	—	$	24	$	—	$	24
Debt securities:
United States government obligations	21		—		—		21
Corporate obligations	—		94		—		94
Municipal obligations	—		10		—		10
Agency, asset and mortgage-backed obligations	—		42		—		42
Equity securities:
United States companies	355		—		—		355
International companies	15		—		—		15
Investment funds(2)	55		—		—		55
Total assets in the fair value hierarchy	$	446	$	170	$	—	616
Investment funds(2) measured at net asset value							327
Limited partnership interests(3) measured at net asset value							93
Investments at fair value							$	1,036
As of December 31, 2018:
Cash equivalents	$	—	$	11	$	—	$	11
Debt securities:
United States government obligations	4		—		—		4
International government obligations			1				1
Corporate obligations	—		88		—		88
Municipal obligations	—		10		—		10
Agency, asset and mortgage-backed obligations	—		43		—		43
Equity securities:
United States companies	327		—		—		327
International companies	15		—		—		15
Investment funds(2)	54		—		—		54
Total assets in the fair value hierarchy	$	400	$	153	$	—	553
Investment funds(2) measured at net asset value							285
Limited partnership interests(3) measured at net asset value							104
Investments at fair value							$	942

(1) Refer to Note 13 for additional discussion regarding the three levels of the fair value hierarchy.

(2) Investment funds are substantially comprised of mutual funds and collective trust funds. These funds consist of equity and debt securities of approximately55% and 45% respectively, for both 2019 and 2018, and are invested in United States and international securities of approximately 51% and 49%, respectively, for 2019 and 68% and 32%, respectively, for 2018.

(3) Limited partnership interests include several funds that invest primarily in real estate, buyout, growth equity and venture capital.

The following table presents the fair value of plan assets, by major category, for PacifiCorp's defined benefit other postretirement plan (in millions):

	Input Levels for Fair Value Measurements
	Level 1(1)		Level 2(1)		Level 3(1)		Total
As of December 31, 2019:
Cash and cash equivalents	$	8	$	1	$	—	$	9
Debt securities:
United States government obligations	12		—		—		12
Corporate obligations	—		26		—		26
Municipal obligations	—		2		—		2
Agency, asset and mortgage-backed obligations	—		22		—		22
Equity securities:
United States companies	74		—		—		74
International companies	4		—		—		4
Investment funds(2)	44		—		—		44
Total assets in the fair value hierarchy	142		51		—		193
Investment funds(2) measured at net asset value							136
Limited partnership interests(3) measured at net asset value							5
Investments at fair value							$	334
As of December 31, 2018:
Cash and cash equivalents	$	4	$	1	$	—	$	5
Debt securities:
United States government obligations	3		—		—		3
Corporate obligations	—		23		—		23
Municipal obligations	—		2		—		2
Agency, asset and mortgage-backed obligations	—		17		—		17
Equity securities:
United States companies	83		—		—		83
International companies	4		—		—		4
Investment funds(2)	38		—		—		38
Total assets in the fair value hierarchy	132		43		—		175
Investment funds(2) measured at net asset value							116
Limited partnership interests(3) measured at net asset value							6
Investments at fair value							$	297

(1) Refer to Note 13 for additional discussion regarding the three levels of the fair value hierarchy.

(2) Investment funds are substantially comprised of mutual funds and collective trust funds. These funds consist of equity and debt securities of approximately56% and 44%, respectively, for 2019 and 59% and 41%, respectively, for 2018, and are invested in United States and international securities of approximately 79% and 21%, respectively, for 2019 and 90% and 10%, respectively, for 2018.

(3) Limited partnership interests include several funds that invest primarily in real estate, buyout, growth equity and venture capital.

The following table presents PacifiCorp's assets and liabilities recognized on the Consolidated Balance Sheets and measured at fair value on a recurring basis (in millions):

	Input Levels for Fair Value Measurements
	Level 1		Level 2			Level 3		Other(1)			Total
As of December 31, 2019:
Assets:
Commodity derivatives	$	—	$	21		$	—	$	(7	)	$	14
Money market mutual funds(2)	23		—			—		—			23
Investment funds	25		—			—		—			25
	$	48	$	21		$	—	$	(7	)	$	62
Liabilities - Commodity derivatives	$	—	$	(84	)	$	—	$	54		$	(30	)
As of December 31, 2018:
Assets:
Commodity derivatives	$	—	$	51		$	—	$	(23	)	$	28
Money market mutual funds (2)	69		—			—		—			69
Investment funds	24		—			—		—			24
	$	93	$	51		$	—	$	(23	)	$	121
Liabilities - Commodity derivatives	$	—	$	(148	)	$	—	$	82		$	(66	)

(1) Represents netting under master netting arrangements and a net cash collateral receivable of $47 million and $59 million as of December 31, 2019 and 2018, respectively.

(2) Amounts are included in cash and cash equivalents, other current assets and other assets on the Consolidated Balance Sheets. The fair value of these money market mutual funds approximates cost.

Schedule of Multiemployer Plans [Table Text Block]

The following table presents PacifiCorp's participation in individually significant joint trustee and multiemployer pension plans for the years ended December 31 (dollars in millions):

		PPA zone status or
		plan funded status percentage for
		plan years beginning July 1,					Contributions(1)
Plan name	Employer Identification Number	2019	2018	2017	Funding improvement plan	Surcharge imposed under PPA(1)	2019		2018		2017		Year contributions to plan exceeded more than 5% of total contributions(2)
Local 57 Trust Fund	87-0640888	At least 80%	At least 80%	At least 80%	None	None	$	7	$	7	$	7	2017, 2016, 2015

(1) PacifiCorp's minimum contributions to the plan are based on the amount of wages paid to employees covered by the Local 57 Trust Fund collective bargaining agreements, subject to ERISA minimum funding requirements.

(2) For the Local 57 Trust Fund, information is for plan years beginning July 1, 2017, 2016 and 2015. Information for the plan year beginning July 1, 2018 is not yet available.

MidAmerican Energy Company [Member]

Defined Benefit Plan Disclosure [Line Items]

Schedule of Net Benefit Costs [Table Text Block]

Net periodic benefit cost for the plans of MidAmerican Energy and the aforementioned affiliates included the following components for the years ended December 31 (in millions):

	Pension									Other Postretirement
	2019			2018			2017			2019			2018			2017
Service cost	$	6		$	9		$	9		$	5		$	5		$	5
Interest cost	30			28			31			10			8			9
Expected return on plan assets	(41		)	(44		)	(44		)	(13		)	(13		)	(14		)
Settlement	—			(1		)	—			—			—			—
Net amortization	1			2			2			(3		)	(4		)	(4		)
Net periodic benefit (credit) cost	$	(4	)	$	(6	)	$	(2	)	$	(1	)	$	(4	)	$	(4	)

Changes in Fair Value of Plan Assets [Table Text Block]

The following table is a reconciliation of the fair value of plan assets for the years ended December 31 (in millions):

	Pension						Other Postretirement
	2019			2018			2019			2018
Plan assets at fair value, beginning of year	$	644		$	745		$	247		$	277
Employer contributions	7			7			1			1
Participant contributions	—			—			2			1
Actual return on plan assets	123			(39		)	42			(17		)
Settlement	—			(37		)	—			—
Benefits paid	(57		)	(32		)	(20		)	(15		)
Plan assets at fair value, end of year	$	717		$	644		$	272		$	247

Changes in Projected Benefit Obligations [Table Text Block]

The following table is a reconciliation of the benefit obligations for the years ended December 31 (in millions):

	Pension						Other Postretirement
	2019			2018			2019			2018
Benefit obligation, beginning of year	$	736		$	799		$	242		$	246
Service cost	6			9			5			5
Interest cost	30			28			10			8
Participant contributions	—			—			2			1
Actuarial (gain) loss	48			(33		)	(13		)	(3		)
Plan amendments	—			2			—			—
Settlement	—			(37		)	—			—
Benefits paid	(57		)	(32		)	(20		)	(15		)
Benefit obligation, end of year	$	763		$	736		$	226		$	242
Accumulated benefit obligation, end of year	$	758		$	733

Benefit Obligations in Excess of Fair Value of Plan Assets [Table Text Block]

The funded status of the plans and the amounts recognized on the Balance Sheets as of December 31 are as follows (in millions):

	Pension						Other Postretirement
	2019			2018			2019		2018
Plan assets at fair value, end of year	$	717		$	644		$	272	$	247
Less - Benefit obligation, end of year	763			736			226		242
Funded status	$	(46	)	$	(92	)	$	46	$	5
Amounts recognized on the Balance Sheets:
Other assets	$	66		$	17		$	46	$	5
Other current liabilities	(7		)	(7		)	—		—
Other liabilities	(105		)	(102		)	—		—
Amounts recognized	$	(46	)	$	(92	)	$	46	$	5

Net Periodic Benefit Costs Not Yet Recognized [Table Text Block]

A reconciliation of the amounts not yet recognized as components of net periodic benefit cost for the years ended December 31, 2019 and 2018 is as follows (in millions):

	Regulatory Asset			Regulatory Liability			Receivables (Payables) with Affiliates		Total
Pension
Balance, December 31, 2017	$	24		$	(41	)	$	7	$	(10	)
Net loss arising during the year	2			41			9		52
Net amortization	(2		)	—			—		(2		)
Settlement	1			—			—		1
Total	1			41			9		51
Balance, December 31, 2018	25			—			16		41
Net (gain) loss arising during the year	(5		)	(32		)	2		(35		)
Net amortization	(1		)	—			—		(1		)
Total	(6		)	(32		)	2		(36		)
Balance, December 31, 2019	$	19		$	(32	)	$	18	$	5

	Regulatory Asset			Receivables (Payables) with Affiliates			Total
Other Postretirement
Balance, December 31, 2017	$	14		$	(16	)	$	(2	)
Net loss arising during the year	20			6			26
Net amortization	3			1			4
Total	23			7			30
Balance, December 31, 2018	37			(9		)	28
Net (gain) arising during the year	(33		)	(9		)	(42		)
Net amortization	3			1			4
Total	(30		)	(8		)	(38		)
Balance, December 31, 2019	$	7		$	(17	)	$	(10	)

The portion of the funded status of the plans not yet recognized in net periodic benefit cost as of December 31 is as follows (in millions):

	Pension					Other Postretirement
	2019			2018		2019			2018
Net loss (gain)	$	6		$	40	$	4		$	48
Prior service cost (credit)	(1		)	1		(14		)	(20		)
Total	$	5		$	41	$	(10	)	$	28

Plan Assumptions [Table Text Block]

Assumptions used to determine benefit obligations and net periodic benefit cost were as follows:

	Pension						Other Postretirement
	2019		2018		2017		2019		2018		2017
Benefit obligations as of December 31:
Discount rate	3.40	%	4.25	%	3.60	%	3.20	%	4.15	%	3.50	%
Rate of compensation increase	2.75	%	2.75	%	2.75	%	N/A		N/A		N/A
Interest crediting rates for cash balance plan
2017	N/A		N/A		1.44	%	N/A		N/A		N/A
2018	N/A		2.26	%	2.26	%	N/A		N/A		N/A
2019	3.40	%	3.40	%	2.26	%	N/A		N/A		N/A
2020	2.27	%	3.40	%	1.60	%	N/A		N/A		N/A
2021	2.27	%	3.40	%	1.60	%	N/A		N/A		N/A
2022 and beyond	2.27	%	3.40	%	1.60	%	N/A		N/A		N/A
Net periodic benefit cost for the years ended December 31:
Discount rate	4.25	%	3.60	%	4.10	%	4.15	%	3.50	%	3.90	%
Expected return on plan assets(1)	6.50	%	6.50	%	6.75	%	6.25	%	6.25	%	6.50	%
Rate of compensation increase	2.75	%	2.75	%	2.75	%	N/A		N/A		N/A
Interest crediting rates for cash balance plan	3.40	%	2.26	%	1.44	%	N/A		N/A		N/A

(1) Amounts reflected are pre-tax values. Assumed after-tax returns for a taxable, non-union other postretirement plan were 4.62% for 2019, 4.13% for 2018, and 4.81% for 2017.

In establishing its assumption as to the expected return on plan assets, MidAmerican Energy utilizes the asset allocation and return assumptions for each asset class based on historical performance and forward-looking views of the financial markets.

	2019		2018
Assumed healthcare cost trend rates as of December 31:
Healthcare cost trend rate assumed for next year	6.50	%	6.80	%
Rate that the cost trend rate gradually declines to	5.00	%	5.00	%
Year that the rate reaches the rate it is assumed to remain at	2025		2025

Expected Benefit Payments [Table Text Block]

Net periodic benefit costs assigned to MidAmerican Energy affiliates are reimbursed currently in accordance with its intercompany administrative services agreement. The expected benefit payments to participants in MidAmerican Energy's pension and other postretirement benefit plans for 2020 through 2024 and for the five years thereafter are summarized below (in millions):

	Projected Benefit Payments
	Pension		Other Postretirement
2020	$	64	$	20
2021	63		22
2022	61		22
2023	58		21
2024	56		20
2025-2029	244		84

Allocation of Plan Assets [Table Text Block]

The target allocations (percentage of plan assets) for MidAmerican Energy's pension and other postretirement benefit plan assets are as follows as of December 31, 2019:

	Pension	Other Postretirement
	%	%
Debt securities(1)	20-50	25-45
Equity securities(1)	60-80	45-80
Real estate funds	2-8	—
Other	0-3	0-5

(1) For purposes of target allocation percentages and consistent with the plans' investment policy, investment funds are allocated based on the underlying investments in debt and equity securities.

Fair Value, Assets and Liabilities Measured on Recurring Basis [Table Text Block]

The following table presents the fair value of plan assets, by major category, for MidAmerican Energy's defined benefit pension plan (in millions):

	Input Levels for Fair Value Measurements(1)
	Level 1		Level 2		Level 3		Total
As of December 31, 2019:
Cash equivalents	$	21	$	—	$	—	$	21
Debt securities:
United States government obligations	16		—		—		16
Corporate obligations	—		61		—		61
Municipal obligations	—		5		—		5
Agency, asset and mortgage-backed obligations	—		33		—		33
Equity securities:
United States companies	129		—		—		129
International companies	42		—		—		42
Investment funds(2)	69		—		—		69
Total assets in the hierarchy	$	277	$	99	$	—	376
Investment funds(2) measured at net asset value							299
Real estate funds measured at net asset value							42
Total assets measured at fair value							$	717
As of December 31, 2018:
Cash equivalents	$	—	$	20	$	—	$	20
Debt securities:
United States government obligations	6		—		—		6
Corporate obligations	—		63		—		63
Municipal obligations	—		6		—		6
Agency, asset and mortgage-backed obligations	—		37		—		37
Equity securities:
United States companies	111		—		—		111
International companies	35		—		—		35
Investment funds(2)	65		—		—		65
Total assets in the hierarchy	$	217	$	126	$	—	343
Investment funds(2) measured at net asset value							260
Real estate funds measured at net asset value							41
Total assets measured at fair value							$	644

(1) Refer to Note 12 for additional discussion regarding the three levels of the fair value hierarchy.

(2) Investment funds are comprised of mutual funds and collective trust funds. These funds consist of equity and debt securities of approximately 69% and 31%, respectively, for 2019 and 65% and 35%, respectively, for 2018. Additionally, these funds are invested in United States and international securities of approximately 74% and 26%, respectively, for 2019 and 74% and 26%, respectively, for 2018.

The following table presents the fair value of plan assets, by major category, for MidAmerican Energy's defined benefit other postretirement plans (in millions):

	Input Levels for Fair Value Measurements(1)
	Level 1		Level 2		Level 3		Total
As of December 31, 2019:
Cash equivalents	$	6	$	—	$	—	$	6
Debt securities:
United States government obligations	6		—		—		6
Corporate obligations	—		12		—		12
Municipal obligations	—		55		—		55
Agency, asset and mortgage-backed obligations	—		10		—		10
Equity securities:
United States companies	75		—		—		75
Investment funds(2)	108		—		—		108
Total assets measured at fair value	$	195	$	77	$	—	$	272
As of December 31, 2018:
Cash equivalents	$	5	$	—	$	—	$	5
Debt securities:
United States government obligations	6		—		—		6
Corporate obligations	—		12		—		12
Municipal obligations	—		43		—		43
Agency, asset and mortgage-backed obligations	—		12		—		12
Equity securities:
United States companies	73		—		—		73
Investment funds(2)	96		—		—		96
Total assets measured at fair value	$	180	$	67	$	—	$	247

(1) Refer to Note 12 for additional discussion regarding the three levels of the fair value hierarchy.

(2) Investment funds are comprised of mutual funds and collective trust funds. These funds consist of equity and debt securities of approximately 77% and 23%, respectively, for 2019 and 78% and 22%, respectively, for 2018. Additionally, these funds are invested in United States and international securities of approximately 42% and 58%, respectively, for 2019 and 41% and 59%, respectively, for 2018.

The following table presents MidAmerican Energy's assets and liabilities recognized on the Balance Sheets and measured at fair value on a recurring basis (in millions):

	Input Levels for Fair Value Measurements
	Level 1		Level 2			Level 3			Other(1)			Total
As of December 31, 2019:
Assets:
Commodity derivatives	$	—	$	2		$	1		$	(1	)	$	2
Money market mutual funds(2)	274		—			—			—			274
Debt securities:
United States government obligations	189		—			—			—			189
International government obligations	—		4			—			—			4
Corporate obligations	—		58			—			—			58
Municipal obligations	—		1			—			—			1
Agency, asset and mortgage-backed obligations	—		1			—			—			1
Equity securities:
United States companies	336		—			—			—			336
International companies	9		—			—			—			9
Investment funds	15		—			—			—			15
	$	823	$	66		$	1		$	(1	)	$	889
Liabilities - commodity derivatives	$	—	$	(9	)	$	—		$	2		$	(7	)
As of December 31, 2018
Assets:
Commodity derivatives	$	—	$	4		$	2		$	(3	)	$	3
Money market mutual funds(2)	2		—			—			—			2
Debt securities:
United States government obligations	187		—			—			—			187
International government obligations	—		4			—			—			4
Corporate obligations	—		46			—			—			46
Municipal obligations	—		2			—			—			2
Agency, asset and mortgage-backed obligations	—		1			—			—			1
Equity securities:
United States companies	256		—			—			—			256
International companies	6		—			—			—			6
Investment funds	10		—			—			—			10
	$	461	$	57		$	2		$	(3	)	$	517
Liabilities:
Commodity derivatives	$	—	$	(4	)	$	(2	)	$	3		$	(3	)
Interest rate derivatives(3)	$	—	$	(19	)	$	—		$	—		$	(19	)
	$	—	$	(23	)	$	(2	)	$	3		$	(22	)

(1) Represents netting under master netting arrangements and a net cash collateral receivable of $1 million and $- million as of December 31, 2019 and 2018, respectively.

(2) Amounts are included in cash and cash equivalents and investments and restricted investments on the Balance Sheets. The fair value of these money market mutual funds approximates cost.

(3) The interest rate derivatives were interest rate locks related to MidAmerican Energy's January 2019 issuance of first mortgage bonds.

MidAmerican Funding, LLC and Subsidiaries [Domain]

Defined Benefit Plan Disclosure [Line Items]

Schedule of Net Benefit Costs [Table Text Block]

Pension and postretirement costs allocated by MidAmerican Funding to its parent and other affiliates in each of the years ended December 31, were as follows (in millions):

	2019			2018			2017
Pension costs	$	4		$	3		$	4
Other postretirement costs	(2		)	(2		)	(3		)