Weighted average rates assumed in actuarial calculations used to determine both benefit obligations as of measurement date and net periodic costs for pension and other postretirement benefit plans

Actuarial Assumptions

The weighted average rates assumed in the actuarial calculations used to determine both the net periodic costs for the pension and other postretirement benefit plans for the following year and the benefit obligations as of the measurement date are presented below.



Assumptions used to determine net periodic costs:	2015		2014		2013
Pension plans
Discount rate – interest costs	4.17	%	5.02	%	4.26	%
Discount rate – service costs	4.48		5.02		4.26
Expected long-term return on plan assets	8.20		8.20		8.20
Annual salary increase	3.59		3.59		3.59
Other postretirement benefit plans
Discount rate – interest costs	4.04	%	4.85	%	4.05	%
Discount rate – service costs	4.39		4.85		4.05
Expected long-term return on plan assets	6.97		7.15		7.13
Annual salary increase	3.59		3.59		3.59



Assumptions used to determine benefit obligations:	2015		2014
Pension plans
Discount rate	4.67	%	4.17	%
Annual salary increase	4.46		3.59
Other postretirement benefit plans
Discount rate	4.51	%	4.04	%
Annual salary increase	4.46		3.59

Effect of 1% annual increase or decrease in assumed medical care cost on APBO and service and interest cost components

The weighted average medical care cost trend rates used in measuring the APBO as of December 31, 2015 were as follows:



	Initial Cost Trend Rate		Ultimate Cost Trend Rate		Year That Ultimate Rate is Reached
Pre-65	6.50	%	4.50	%	2024
Post-65 medical	5.50		4.50		2024
Post-65 prescription	10.00		4.50		2025

An annual increase or decrease in the assumed medical care cost trend rate of 1% would affect the APBO and the service and interest cost components at December 31, 2015 as follows:



	1 Percent Increase		1 Percent Decrease
	(in millions)
Benefit obligation	$	119	$	(102	)
Service and interest costs	4		(4		)

Changes in projected benefit obligations and fair value of plan assets

Changes in the projected benefit obligations and the fair value of plan assets during the plan years ended December 31, 2015 and 2014 were as follows:



	2015			2014
	(in millions)
Change in benefit obligation
Benefit obligation at beginning of year	$	10,909		$	8,863
Service cost	257			213
Interest cost	445			435
Benefits paid	(487		)	(382		)
Actuarial loss (gain)	(582		)	1,780
Balance at end of year	10,542			10,909
Change in plan assets
Fair value of plan assets at beginning of year	9,690			8,733
Actual return (loss) on plan assets	(14		)	797
Employer contributions	45			542
Benefits paid	(487		)	(382		)
Fair value of plan assets at end of year	9,234			9,690
Accrued liability	$	(1,308	)	$	(1,219	)

Presented below are the amounts included in accumulated OCI and regulatory assets at December 31, 2015 and 2014 related to the defined benefit pension plans that had not yet been recognized in net periodic pension cost along with the estimated amortization of such amounts for 2016.



	Prior Service Cost		Net (Gain) Loss
	(in millions)
Balance at December 31, 2015:
Accumulated OCI	$	3	$	122
Regulatory assets	27		2,971
Total	$	30	$	3,093
Balance at December 31, 2014:
Accumulated OCI	$	4	$	130
Regulatory assets	51		3,022
Total	$	55	$	3,152
Estimated amortization in net periodic pension cost in 2016:
Accumulated OCI	$	1	$	6
Regulatory assets	13		145
Total	$	14	$	151

Components of other comprehensive income along with changes in balances of regulatory assets and regulatory liabilities related to defined benefit pension plans

The components of OCI and the changes in the balance of regulatory assets related to the defined benefit pension plans for the years ended December 31, 2015 and 2014 are presented in the following table:



	Accumulated OCI			Regulatory Assets
	(in millions)
Balance at December 31, 2013	$	64		$	1,651
Net gain	75			1,552
Change in prior service costs	—			1
Reclassification adjustments:
Amortization of prior service costs	(1		)	(25		)
Amortization of net gain	(4		)	(106		)
Total reclassification adjustments	(5		)	(131		)
Total change	70			1,422
Balance at December 31, 2014	$	134		$	3,073
Net loss	1			155
Reclassification adjustments:
Amortization of prior service costs	(1		)	(24		)
Amortization of net gain	(9		)	(206		)
Total reclassification adjustments	(10		)	(230		)
Total change	(9		)	(75		)
Balance at December 31, 2015	$	125		$	2,998

Changes in the accumulated postretirement benefit obligations (APBO) and in fair value of plan assets

At December 31, 2015, estimated benefit payments were as follows:



	Benefit Payments
	(in millions)
2016	$	450
2017	478
2018	501
2019	527
2020	554
2021 to 2025	3,141

Changes in the APBO and in the fair value of plan assets during the plan years ended December 31, 2015 and 2014 were as follows:



	2015			2014
	(in millions)
Change in benefit obligation
Benefit obligation at beginning of year	$	1,986		$	1,682
Service cost	23			21
Interest cost	78			79
Benefits paid	(102		)	(102		)
Actuarial loss (gain)	(38		)	300
Plan amendments	34			(2		)
Retiree drug subsidy	8			8
Balance at end of year	1,989			1,986
Change in plan assets
Fair value of plan assets at beginning of year	900			901
Actual return (loss) on plan assets	(12		)	54
Employer contributions	39			39
Benefits paid	(94		)	(94		)
Fair value of plan assets at end of year	833			900
Accrued liability	$	(1,156	)	$	(1,086	)

Amounts included in accumulated other comprehensive income and regulatory assets related to other postretirement benefit plans

Presented below are the amounts included in accumulated OCI and net regulatory assets (liabilities) at December 31, 2015 and 2014 related to the other postretirement benefit plans that had not yet been recognized in net periodic other postretirement benefit cost along with the estimated amortization of such amounts for 2016.



	Prior Service Cost		Net (Gain) Loss
	(in millions)
Balance at December 31, 2015:
Accumulated OCI	$	—	$	8
Net regulatory assets	32		379
Total	$	32	$	387
Balance at December 31, 2014:
Accumulated OCI	$	—	$	8
Net regulatory assets	2		364
Total	$	2	$	372
Estimated amortization as net periodic postretirement benefit cost in 2016:
Net regulatory assets	$	6	$	14

Components of other comprehensive income along with changes in balance of regulatory assets related to other postretirement benefit plans

The components of OCI, along with the changes in the balance of net regulatory assets (liabilities), related to the other postretirement benefit plans for the plan years ended December 31, 2015 and 2014 are presented in the following table:



	Accumulated OCI		Net Regulatory Assets (Liabilities)
	(in millions)
Balance at December 31, 2013	$	1	$	73
Net gain	7		301
Change in prior service costs	—		(2		)
Reclassification adjustments:
Amortization of prior service costs	—		(4		)
Amortization of net gain	—		(2		)
Total reclassification adjustments	—		(6		)
Total change	7		293
Balance at December 31, 2014	$	8	$	366
Net gain	—		33
Change in prior service costs	—		33
Reclassification adjustments:
Amortization of prior service costs	—		(4		)
Amortization of net gain	—		(17		)
Total reclassification adjustments	—		(21		)
Total change	—		45
Balance at December 31, 2015	$	8	$	411

Summary of estimation of future benefit payments and subsidy receipts based on assumptions used to measure accumulated benefit obligation for postretirement plans

Estimated benefit payments are reduced by drug subsidy receipts expected as a result of the Medicare Prescription Drug, Improvement, and Modernization Act of 2003 as follows:



	Benefit Payments		Subsidy Receipts			Total
	(in millions)
2016	$	123	$	(9	)	$	114
2017	128		(10		)	118
2018	133		(11		)	122
2019	137		(12		)	125
2020	139		(12		)	127
2021 to 2025	711		(65		)	646

Composition of benefit plan assets along with targeted mix of assets

The composition of the Company's pension plan and other postretirement benefit plan assets as of December 31, 2015 and 2014, along with the targeted mix of assets for each plan, is presented below:



	Target		2015		2014
Pension plan assets:
Domestic equity	26	%	30	%	30	%
International equity	25		23		23
Fixed income	23		23		27
Special situations	3		2		1
Real estate investments	14		16		14
Private equity	9		6		5
Total	100	%	100	%	100	%
Other postretirement benefit plan assets:
Domestic equity	42	%	38	%	41	%
International equity	21		23		23
Domestic fixed income	24		26		26
Global fixed income	4		4		3
Special situations	1		1		—
Real estate investments	5		6		5
Private equity	3		2		2
Total	100	%	100	%	100	%

Pension Plans [Member]

Amounts recognized in balance sheets related to benefit plans

Amounts recognized in the balance sheets at December 31, 2015 and 2014 related to the Company's pension plans consist of the following:



	2015			2014
	(in millions)
Other regulatory assets, deferred	$	2,998		$	3,073
Other current liabilities	(46		)	(42		)
Employee benefit obligations	(1,262		)	(1,177		)
Accumulated OCI	125			134

Components of net periodic pension cost were as follows:



	2015			2014			2013
	(in millions)
Service cost	$	257		$	213		$	232
Interest cost	445			435			389
Expected return on plan assets	(724		)	(645		)	(603		)
Recognized net loss	215			110			200
Net amortization	25			26			27
Net periodic pension cost	$	218		$	139		$	245

Other Postretirement Benefits [Member]

The fair values of pension plan assets as of December 31, 2015 and 2014 are presented below. These fair value measurements exclude cash, receivables related to investment income, pending investments sales, and payables related to pending investment purchases. Assets that are considered special situations investments, primarily real estate investments and private equities, are presented in the tables below based on the nature of the investment.



	Fair Value Measurements Using
	Quoted Prices in Active Markets for Identical Assets			Significant Other Observable Inputs		Significant Unobservable Inputs		Net Asset Value as a Practical Expedient
As of December 31, 2015:	(Level 1)			(Level 2)		(Level 3)		(NAV)		Total
	(in millions)
Assets:
Domestic equity*	$	1,632		$	681	$	—	$	—	$	2,313
International equity*	1,190			990		—		—		2,180
Fixed income:
U.S. Treasury, government, and agency bonds	—			454		—		—		454
Mortgage- and asset-backed securities	—			199		—		—		199
Corporate bonds	—			1,140		—		—		1,140
Pooled funds	—			500		—		—		500
Cash equivalents and other	—			145		—		—		145
Real estate investments	299			—		—		1,218		1,517
Private equity	—			—		—		635		635
Total	$	3,121		$	4,109	$	—	$	1,853	$	9,083
Liabilities:
Derivatives	$	(1	)	$	—	$	—	$	—	$	(1	)
Total	$	3,120		$	4,109	$	—	$	1,853	$	9,082



*	Level 1 securities consist of actively traded stocks while Level 2 securities consist of pooled funds. Management believes that the portfolio is well-diversified with no significant concentrations of risk.



	Fair Value Measurements Using
	Quoted Prices in Active Markets for Identical Assets			Significant Other Observable Inputs		Significant Unobservable Inputs		Net Asset Value as a Practical Expedient
As of December 31, 2014:	(Level 1)			(Level 2)		(Level 3)		(NAV)		Total
	(in millions)
Assets:
Domestic equity*	$	1,704		$	704	$	—	$	—	$	2,408
International equity*	1,070			986		—		—		2,056
Fixed income:
U.S. Treasury, government, and agency bonds	—			699		—		—		699
Mortgage- and asset-backed securities	—			188		—		—		188
Corporate bonds	—			1,135		—		—		1,135
Pooled funds	—			514		—		—		514
Cash equivalents and other	3			660		—		—		663
Real estate investments	293			—		—		1,121		1,414
Private equity	—			—		—		570		570
Total	$	3,070		$	4,886	$	—	$	1,691	$	9,647
Liabilities:
Derivatives	$	(2	)	$	—	$	—	$	—	$	(2	)
Total	$	3,068		$	4,886	$	—	$	1,691	$	9,645



*	Level 1 securities consist of actively traded stocks while Level 2 securities consist of pooled funds. Management believes that the portfolio is well-diversified with no significant concentrations of risk.

Amounts recognized in balance sheets related to benefit plans

Amounts recognized in the balance sheets at December 31, 2015 and 2014 related to the Company's other postretirement benefit plans consist of the following:



	2015			2014
	(in millions)
Other regulatory assets, deferred	$	433		$	387
Other current liabilities	(4		)	(4		)
Employee benefit obligations	(1,152		)	(1,082		)
Other regulatory liabilities, deferred	(22		)	(21		)
Accumulated OCI	8			8

Components of the other postretirement benefit plans' net periodic cost were as follows:



	2015			2014			2013
	(in millions)
Service cost	$	23		$	21		$	24
Interest cost	78			79			74
Expected return on plan assets	(58		)	(59		)	(56		)
Net amortization	21			6			21
Net periodic postretirement benefit cost	$	64		$	47		$	63

Assets that are considered special situations investments, primarily real estate investments and private equities, are presented in the tables below based on the nature of the investment.



	Fair Value Measurements Using
	Quoted Prices in Active Markets for Identical Assets		Significant Other Observable Inputs		Significant Unobservable Inputs		Net Asset Value as a Practical Expedient		Total
As of December 31, 2015:	(Level 1)		(Level 2)		(Level 3)		(NAV)
	(in millions)
Assets:
Domestic equity*	$	106	$	52	$	—	$	—	$	158
International equity*	40		64		—		—		104
Fixed income:
U.S. Treasury, government, and agency bonds	—		22		—		—		22
Mortgage- and asset-backed securities	—		7		—		—		7
Corporate bonds	—		38		—		—		38
Pooled funds	—		42		—		—		42
Cash equivalents and other	11		9		—		—		20
Trust-owned life insurance	—		370		—		—		370
Real estate investments	11		—		—		41		52
Private equity	—		—		—		21		21
Total	$	168	$	604	$	—	$	62	$	834



*	Level 1 securities consist of actively traded stocks while Level 2 securities consist of pooled funds. Management believes that the portfolio is well-diversified with no significant concentrations of risk.



	Fair Value Measurements Using
	Quoted Prices in Active Markets for Identical Assets		Significant Other Observable Inputs		Significant Unobservable Inputs		Net Asset Value as a Practical Expedient
As of December 31, 2014:	(Level 1)		(Level 2)		(Level 3)		(NAV)		Total
	(in millions)
Assets:
Domestic equity*	$	147	$	56	$	—	$	—	$	203
International equity*	36		67		—		—		103
Fixed income:
U.S. Treasury, government, and agency bonds	—		29		—		—		29
Mortgage- and asset-backed securities	—		6		—		—		6
Corporate bonds	—		39		—		—		39
Pooled funds	—		41		—		—		41
Cash equivalents and other	9		27		—		—		36
Trust-owned life insurance	—		381		—		—		381
Real estate investments	11		—		—		37		48
Private equity	—		—		—		19		19
Total	$	203	$	646	$	—	$	56	$	905



*	Level 1 securities consist of actively traded stocks while Level 2 securities consist of pooled funds. Management believes that the portfolio is well-diversified with no significant concentrations of risk.

Alabama Power [Member]

Weighted average rates assumed in actuarial calculations used to determine both benefit obligations as of measurement date and net periodic costs for pension and other postretirement benefit plans



Assumptions used to determine net periodic costs:	2015		2014		2013
Pension plans
Discount rate – interest costs	4.18	%	5.02	%	4.27	%
Discount rate – service costs	4.49		5.02		4.27
Expected long-term return on plan assets	8.20		8.20		8.20
Annual salary increase	3.59		3.59		3.59
Other postretirement benefit plans
Discount rate – interest costs	4.04	%	4.86	%	4.06	%
Discount rate – service costs	4.40		4.86		4.06
Expected long-term return on plan assets	7.17		7.34		7.36
Annual salary increase	3.59		3.59		3.59



Assumptions used to determine benefit obligations:	2015		2014
Pension plans
Discount rate	4.67	%	4.18	%
Annual salary increase	4.46		3.59
Other postretirement benefit plans
Discount rate	4.51	%	4.04	%
Annual salary increase	4.46		3.59

Effect of 1% annual increase or decrease in assumed medical care cost on APBO and service and interest cost components

The weighted average medical care cost trend rates used in measuring the APBO as of December 31, 2015 were as follows:



	Initial Cost Trend Rate		Ultimate Cost Trend Rate		Year That Ultimate Rate is Reached
Pre-65	6.50	%	4.50	%	2024
Post-65 medical	5.50		4.50		2024
Post-65 prescription	10.00		4.50		2025

An annual increase or decrease in the assumed medical care cost trend rate of 1% would affect the APBO and the service and interest cost components at December 31, 2015 as follows:



	1 Percent Increase		1 Percent Decrease
	(in millions)
Benefit obligation	$	29	$	(25	)
Service and interest costs	1		(1		)

Changes in projected benefit obligations and fair value of plan assets

Changes in the projected benefit obligations and the fair value of plan assets during the plan years ended December 31, 2015 and 2014 were as follows:



	2015			2014
	(in millions)
Change in benefit obligation
Benefit obligation at beginning of year	$	2,592		$	2,112
Service cost	59			48
Interest cost	106			103
Benefits paid	(120		)	(100		)
Actuarial loss (gain)	(131		)	429
Balance at end of year	2,506			2,592
Change in plan assets
Fair value of plan assets at beginning of year	2,396			2,278
Actual return (loss) on plan assets	(9		)	207
Employer contributions	12			11
Benefits paid	(120		)	(100		)
Fair value of plan assets at end of year	2,279			2,396
Accrued liability	$	(227	)	$	(196	)

Amounts recognized in balance sheets related to benefit plans

Amounts recognized in the balance sheets at December 31, 2015 and 2014 related to the Company's other postretirement benefit plans consist of the following:



	2015			2014
	(in millions)
Other regulatory assets, deferred	$	95		$	68
Other regulatory liabilities, deferred	(13		)	(14		)
Employee benefit obligations	(142		)	(111		)

Amounts recognized in the balance sheets at December 31, 2015 and 2014 related to the Company's pension plans consist of the following:



	2015			2014
	(in millions)
Other regulatory assets, deferred	$	822		$	827
Other current liabilities	(11		)	(10		)
Employee benefit obligations	(216		)	(186		)

Presented below are the amounts included in net regulatory assets (liabilities) at December 31, 2015 and 2014 related to the other postretirement benefit plans that had not yet been recognized in net periodic other postretirement benefit cost along with the estimated amortization of such amounts for 2016.



	2015		2014		Estimated Amortization in 2016
	(in millions)
Prior service cost	$	19	$	15	$	4
Net (gain) loss	63		39		2
Net regulatory assets	$	82	$	54

Presented below are the amounts included in regulatory assets at December 31, 2015 and 2014 related to the defined benefit pension plans that had not yet been recognized in net periodic pension cost along with the estimated amortization of such amounts for 2016.



	2015		2014		Estimated Amortization in 2016
	(in millions)
Prior service cost	$	6	$	12	$	3
Net (gain) loss	816		815		40
Regulatory assets	$	822	$	827

Components of other comprehensive income along with changes in balances of regulatory assets and regulatory liabilities related to defined benefit pension plans

The changes in the balance of net regulatory assets (liabilities) related to the other postretirement benefit plans for the plan years ended December 31, 2015 and 2014 are presented in the following table:



	2015			2014
	(in millions)
Net regulatory assets (liabilities):
Beginning balance	$	54		$	(15	)
Net (gain) loss	25			73
Change in prior service costs	8			—
Reclassification adjustments:
Amortization of prior service costs	(3		)	(4		)
Amortization of net gain (loss)	(2		)	—
Total reclassification adjustments	(5		)	(4		)
Total change	28			69
Ending balance	$	82		$	54

The changes in the balance of regulatory assets related to the defined benefit pension plans for the years ended December 31, 2015 and 2014 are presented in the following table:



	2015			2014
	(in millions)
Regulatory assets:
Beginning balance	$	827		$	476
Net (gain) loss	56			389
Reclassification adjustments:
Amortization of prior service costs	(6		)	(7		)
Amortization of net gain (loss)	(55		)	(31		)
Total reclassification adjustments	(61		)	(38		)
Total change	(5		)	351
Ending balance	$	822		$	827

Components of the other postretirement benefit plans' net periodic cost were as follows:



	2015			2014			2013
	(in millions)
Service cost	$	6		$	5		$	6
Interest cost	20			20			19
Expected return on plan assets	(26		)	(25		)	(23		)
Net amortization	5			4			5
Net periodic postretirement benefit cost	$	5		$	4		$	7

Components of net periodic pension cost were as follows:



	2015			2014			2013
	(in millions)
Service cost	$	59		$	48		$	52
Interest cost	106			103			93
Expected return on plan assets	(178		)	(168		)	(157		)
Recognized net loss	55			31			52
Net amortization	6			7			7
Net periodic pension cost	$	48		$	21		$	47

Changes in the accumulated postretirement benefit obligations (APBO) and in fair value of plan assets

Future benefit payments, including prescription drug benefits, reflect expected future service and are estimated based on assumptions used to measure the APBO for the other postretirement benefit plans. Estimated benefit payments are reduced by drug subsidy receipts expected as a result of the Medicare Prescription Drug, Improvement, and Modernization Act of 2003 as follows:



	Benefit Payments		Subsidy Receipts			Total
	(in millions)
2016	$	33	$	(3	)	$	30
2017	34		(3		)	31
2018	34		(3		)	31
2019	35		(4		)	31
2020	36		(4		)	32
2021 to 2025	184		(20		)	164

At December 31, 2015, estimated benefit payments were as follows:



	Benefit Payments
	(in millions)
2016	$	114
2017	119
2018	124
2019	129
2020	134
2021 to 2025	740

Changes in the APBO and in the fair value of plan assets during the plan years ended December 31, 2015 and 2014 were as follows:



	2015			2014
	(in millions)
Change in benefit obligation
Benefit obligation at beginning of year	$	503		$	431
Service cost	6			5
Interest cost	20			20
Benefits paid	(27		)	(27		)
Actuarial loss (gain)	(7		)	71
Plan amendment	7			—
Retiree drug subsidy	3			3
Balance at end of year	505			503
Change in plan assets
Fair value of plan assets at beginning of year	392			389
Actual return (loss) on plan assets	(6		)	23
Employer contributions	1			4
Benefits paid	(24		)	(24		)
Fair value of plan assets at end of year	363			392
Accrued liability	$	(142	)	$	(111	)

Composition of benefit plan assets along with targeted mix of assets

The composition of the Company's pension plan and other postretirement benefit plan assets as of December 31, 2015 and 2014, along with the targeted mix of assets for each plan, is presented below:



	Target		2015		2014
Pension plan assets:
Domestic equity	26	%	30	%	30	%
International equity	25		23		23
Fixed income	23		23		27
Special situations	3		2		1
Real estate investments	14		16		14
Private equity	9		6		5
Total	100	%	100	%	100	%
Other postretirement benefit plan assets:
Domestic equity	48	%	45	%	48	%
International equity	20		20		20
Domestic fixed income	24		27		26
Special situations	1		1		—
Real estate investments	4		5		4
Private equity	3		2		2
Total	100	%	100	%	100	%

Assets that are considered special situations investments, primarily real estate investments and private equities, are presented in the tables below based on the nature of the investment.



	Fair Value Measurements Using
	Quoted Prices in Active Markets for Identical Assets		Significant Other Observable Inputs		Significant Unobservable Inputs		Net Asset Value as a Practical Expedient
As of December 31, 2015:	(Level 1)		(Level 2)		(Level 3)		(NAV)		Total
	(in millions)
Assets:
Domestic equity*	$	57	$	8	$	—	$	—	$	65
International equity*	14		12		—		—		26
Fixed income:
U.S. Treasury, government, and agency bonds	—		8		—		—		8
Mortgage- and asset-backed securities	—		2		—		—		2
Corporate bonds	—		13		—		—		13
Pooled funds	—		6		—		—		6
Cash equivalents and other	1		2		—		—		3
Trust-owned life insurance	—		212		—		—		212
Real estate investments	5		—		—		14		19
Private equity	—		—		—		7		7
Total	$	77	$	263	$	—	$	21	$	361



*	Level 1 securities consist of actively traded stocks while Level 2 securities consist of pooled funds. Management believes that the portfolio is well-diversified with no significant concentrations of risk.



	Fair Value Measurements Using
	Quoted Prices in Active Markets for Identical Assets		Significant Other Observable Inputs		Significant Unobservable Inputs		Net Asset Value as a Practical Expedient
As of December 31, 2014:	(Level 1)		(Level 2)		(Level 3)		(NAV)		Total
	(in millions)
Assets:
Domestic equity*	$	76	$	8	$	—	$	—	$	84
International equity*	13		12		—		—		25
Fixed income:
U.S. Treasury, government, and agency bonds	—		10		—		—		10
Mortgage- and asset-backed securities	—		2		—		—		2
Corporate bonds	—		14		—		—		14
Pooled funds	—		6		—		—		6
Cash equivalents and other	—		8		—		—		8
Trust-owned life insurance	—		217		—		—		217
Real estate investments	5		—		—		13		18
Private equity	—		—		—		7		7
Total	$	94	$	277	$	—	$	20	$	391



*	Level 1 securities consist of actively traded stocks while Level 2 securities consist of pooled funds. Management believes that the portfolio is well-diversified with no significant concentrations of risk.



	Fair Value Measurements Using
	Quoted Prices in Active Markets for Identical Assets		Significant Other Observable Inputs		Significant Unobservable Inputs		Net Asset Value as a Practical Expedient
As of December 31, 2015:	(Level 1)		(Level 2)		(Level 3)		(NAV)		Total
	(in millions)
Assets:
Domestic equity*	$	403	$	168	$	—	$	—	$	571
International equity*	294		244		—		—		538
Fixed income:
U.S. Treasury, government, and agency bonds	—		112		—		—		112
Mortgage- and asset-backed securities	—		49		—		—		49
Corporate bonds	—		280		—		—		280
Pooled funds	—		123		—		—		123
Cash equivalents and other	—		36		—		—		36
Real estate investments	74		—		—		301		375
Private equity	—		—		—		157		157
Total	$	771	$	1,012	$	—	$	458	$	2,241



*	Level 1 securities consist of actively traded stocks while Level 2 securities consist of pooled funds. Management believes that the portfolio is well-diversified with no significant concentrations of risk.



	Fair Value Measurements Using
	Quoted Prices in Active Markets for Identical Assets		Significant Other Observable Inputs		Significant Unobservable Inputs		Net Asset Value as a Practical Expedient
As of December 31, 2014:	(Level 1)		(Level 2)		(Level 3)		(NAV)		Total
	(in millions)
Assets:
Domestic equity*	$	421	$	174	$	—	$	—	$	595
International equity*	264		244		—		—		508
Fixed income:
U.S. Treasury, government, and agency bonds	—		173		—		—		173
Mortgage- and asset-backed securities	—		47		—		—		47
Corporate bonds	—		280		—		—		280
Pooled funds	—		127		—		—		127
Cash equivalents and other	1		163		—		—		164
Real estate investments	73		—		—		277		350
Private equity	—		—		—		141		141
Total	$	759	$	1,208	$	—	$	418	$	2,385



*	Level 1 securities consist of actively traded stocks while Level 2 securities consist of pooled funds. Management believes that the portfolio is well-diversified with no significant concentrations of risk.

Georgia Power [Member]

Weighted average rates assumed in actuarial calculations used to determine both benefit obligations as of measurement date and net periodic costs for pension and other postretirement benefit plans



Assumptions used to determine net periodic costs:	2015		2014		2013
Pension plans
Discount rates – interest costs	4.18	%	5.02	%	4.27	%
Discount rates – service costs	4.49		5.02		4.27
Expected long-term return on plan assets	8.20		8.20		8.20
Annual salary increase	3.59		3.59		3.59
Other postretirement benefit plans
Discount rate – interest costs	4.03	%	4.85	%	4.04	%
Discount rate – service costs	4.39		4.85		4.04
Expected long-term return on plan assets	6.48		6.75		6.74
Annual salary increase	3.59		3.59		3.59



Assumptions used to determine benefit obligations:	2015		2014
Pension plans
Discount rate	4.65	%	4.18	%
Annual salary increase	4.46		3.59
Other postretirement benefit plans
Discount rate	4.49	%	4.03	%
Annual salary increase	4.46		3.59

Effect of 1% annual increase or decrease in assumed medical care cost on APBO and service and interest cost components

The weighted average medical care cost trend rates used in measuring the APBO as of December 31, 2015 were as follows:



	Initial Cost Trend Rate		Ultimate Cost Trend Rate		Year That Ultimate Rate is Reached
Pre-65	6.50	%	4.50	%	2024
Post-65 medical	5.50		4.50		2024
Post-65 prescription	10.00		4.50		2025

An annual increase or decrease in the assumed medical care cost trend rate of 1% would affect the APBO and the service and interest cost components at December 31, 2015 as follows:



	1 Percent Increase		1 Percent Decrease
	(in millions)
Benefit obligation	$	58	$	(50	)
Service and interest costs	2		(2		)

Changes in projected benefit obligations and fair value of plan assets

Changes in the projected benefit obligations and the fair value of plan assets during the plan years ended December 31, 2015 and 2014 were as follows:



	2015			2014
	(in millions)
Change in benefit obligation
Benefit obligation at beginning of year	$	3,781		$	3,116
Service cost	73			62
Interest cost	154			153
Benefits paid	(188		)	(149		)
Actuarial loss (gain)	(205		)	599
Balance at end of year	3,615			3,781
Change in plan assets
Fair value of plan assets at beginning of year	3,383			3,085
Actual return (loss) on plan assets	(13		)	285
Employer contributions	14			162
Benefits paid	(188		)	(149		)
Fair value of plan assets at end of year	3,196			3,383
Accrued liability	$	(419	)	$	(398	)

Amounts recognized in balance sheets related to benefit plans

Amounts recognized in the balance sheets at December 31, 2015 and 2014 related to the Company's other postretirement benefit plans consist of the following:



	2015			2014
	(in millions)
Other regulatory assets, deferred	$	223		$	213
Employee benefit obligations	(496		)	(469		)

Amounts recognized in the balance sheets at December 31, 2015 and 2014 related to the Company's pension plans consist of the following:



	2015			2014
	(in millions)
Other regulatory assets, deferred	$	1,076		$	1,102
Current liabilities, other	(13		)	(12		)
Employee benefit obligations	(406		)	(386		)



	2015		2014		Estimated Amortization in 2016
	(in millions)
Prior service cost	$	8	$	17	$	5
Net (gain) loss	1,068		1,085		55
Regulatory assets	$	1,076	$	1,102

Presented below are the amounts included in regulatory assets at December 31, 2015 and 2014 related to the other postretirement benefit plans that had not yet been recognized in net periodic other postretirement benefit cost along with the estimated amortization of such amounts for 2016.



	2015		2014			Estimated Amortization in 2016
	(in millions)
Prior service cost	$	8	$	(5	)	$	1
Net (gain) loss	215		218			9
Regulatory assets	$	223	$	213

Components of other comprehensive income along with changes in balances of regulatory assets and regulatory liabilities related to defined benefit pension plans

The changes in the balance of regulatory assets related to the defined benefit pension plans for the years ended December 31, 2015 and 2014 are presented in the following table:



	2015			2014
	(in millions)
Regulatory assets:
Beginning balance	$	1,102		$	610
Net (gain) loss	59			543
Reclassification adjustments:
Amortization of prior service costs	(9		)	(10		)
Amortization of net gain (loss)	(76		)	(41		)
Total reclassification adjustments	(85		)	(51		)
Total change	(26		)	492
Ending balance	$	1,076		$	1,102

Components of the other postretirement benefit plans' net periodic cost were as follows:



	2015			2014			2013
	(in millions)
Service cost	$	7		$	6		$	7
Interest cost	34			34			31
Expected return on plan assets	(24		)	(25		)	(24		)
Net amortization	11			2			12
Net periodic postretirement benefit cost	$	28		$	17		$	26

Components of net periodic pension cost were as follows:



	2015			2014			2013
	(in millions)
Service cost	$	73		$	62		$	69
Interest cost	154			153			138
Expected return on plan assets	(251		)	(228		)	(212		)
Recognized net loss	76			41			74
Net amortization	9			10			10
Net periodic pension cost	$	61		$	38		$	79

Changes in the accumulated postretirement benefit obligations (APBO) and in fair value of plan assets

At December 31, 2015, estimated benefit payments were as follows:



	Benefit Payments
	(in millions)
2016	$	168
2017	176
2018	183
2019	189
2020	197
2021 to 2025	1,085

Changes in the APBO and in the fair value of plan assets during the plan years ended December 31, 2015 and 2014 were as follows:



	2015			2014
	(in millions)
Change in benefit obligation
Benefit obligation at beginning of year	$	864		$	723
Service cost	7			6
Interest cost	34			34
Benefits paid	(45		)	(44		)
Actuarial loss (gain)	(22		)	142
Plan amendment	12			—
Retiree drug subsidy	4			3
Balance at end of year	854			864
Change in plan assets
Fair value of plan assets at beginning of year	395			407
Actual return (loss) on plan assets	(6		)	21
Employer contributions	10			8
Benefits paid	(41		)	(41		)
Fair value of plan assets at end of year	358			395
Accrued liability	$	(496	)	$	(469	)

Components of other comprehensive income along with changes in balance of regulatory assets related to other postretirement benefit plans

The changes in the balance of regulatory assets related to the other postretirement benefit plans for the plan years ended December 31, 2015 and 2014 are presented in the following table:



	2015			2014
	(in millions)
Regulatory assets:
Beginning balance	$	213		$	69
Net (gain) loss	9			146
Change in prior service costs	12			—
Reclassification adjustments:
Amortization of net gain (loss)	(11		)	(2		)
Total change	10			144
Ending balance	$	223		$	213

Summary of estimation of future benefit payments and subsidy receipts based on assumptions used to measure accumulated benefit obligation for postretirement plans



	Benefit Payments		Subsidy Receipts			Total
	(in millions)
2016	$	53	$	(4	)	$	49
2017	55		(4		)	51
2018	58		(5		)	53
2019	59		(5		)	54
2020	60		(5		)	55
2021 to 2025	305		(28		)	277

Composition of benefit plan assets along with targeted mix of assets

The composition of the Company's pension plan and other postretirement benefit plan assets as of December 31, 2015 and 2014, along with the targeted mix of assets for each plan, is presented below:



	Target		2015		2014
Pension plan assets:
Domestic equity	26	%	30	%	30	%
International equity	25		23		23
Fixed income	23		23		27
Special situations	3		2		1
Real estate investments	14		16		14
Private equity	9		6		5
Total	100	%	100	%	100	%
Other postretirement benefit plan assets:
Domestic equity	40	%	34	%	38	%
International equity	21		27		26
Domestic fixed income	23		25		24
Global fixed income	9		8		7
Special situations	1		—		—
Real estate investments	4		4		4
Private equity	2		2		1
Total	100	%	100	%	100	%

The fair values of other postretirement benefit plan assets as of December 31, 2015 and 2014 are presented below. These fair value measurements exclude cash, receivables related to investment income, pending investments sales, and payables related to pending investment purchases. Assets that are considered special situations investments, primarily real estate investments and private equities, are presented in the tables below based on the nature of the investment.



	Fair Value Measurements Using
	Quoted Prices in Active Markets for Identical Assets		Significant Other Observable Inputs		Significant Unobservable Inputs		Net Asset Value as a Practical Expedient
As of December 31, 2015:	(Level 1)		(Level 2)		(Level 3)		(NAV)		Total
	(in millions)
Assets:
Domestic equity*	$	30	$	36	$	—	$	—	$	66
International equity*	12		41		—		—		53
Fixed income:
U.S. Treasury, government, and agency bonds	—		5		—		—		5
Mortgage- and asset-backed securities	—		2		—		—		2
Corporate bonds	—		12		—		—		12
Pooled funds	—		30		—		—		30
Cash equivalents and other	10		6		—		—		16
Trust-owned life insurance	—		158		—		—		158
Real estate investments	3		—		—		12		15
Private equity	—		—		—		7		7
Total	$	55	$	290	$	—	$	19	$	364



*	Level 1 securities consist of actively traded stocks while Level 2 securities consist of pooled funds. Management believes that the portfolio is well-diversified with no significant concentrations of risk.



	Fair Value Measurements Using
	Quoted Prices in Active Markets for Identical Assets		Significant Other Observable Inputs		Significant Unobservable Inputs		Net Asset Value as a Practical Expedient
As of December 31, 2014:	(Level 1)		(Level 2)		(Level 3)		(NAV)		Total
	(in millions)
Assets:
Domestic equity*	$	53	$	40	$	—	$	—	$	93
International equity*	11		45		—		—		56
Fixed income:
U.S. Treasury, government, and agency bonds	—		7		—		—		7
Mortgage- and asset-backed securities	—		2		—		—		2
Corporate bonds	—		12		—		—		12
Pooled funds	—		29		—		—		29
Cash equivalents and other	8		11		—		—		19
Trust-owned life insurance	—		162		—		—		162
Real estate investments	3		—		—		12		15
Private equity	—		—		—		6		6
Total	$	75	$	308	$	—	$	18	$	401



*	Level 1 securities consist of actively traded stocks while Level 2 securities consist of pooled funds. Management believes that the portfolio is well-diversified with no significant concentrations of risk.



	Fair Value Measurements Using
	Quoted Prices in Active Markets for Identical Assets		Significant Other Observable Inputs		Significant Unobservable Inputs		Net Asset Value as a Practical Expedient
As of December 31, 2015:	(Level 1)		(Level 2)		(Level 3)		(NAV)		Total
	(in millions)
Assets:
Domestic equity*	$	565	$	236	$	—	$	—	$	801
International equity*	412		343		—		—		755
Fixed income:
U.S. Treasury, government, and agency bonds	—		157		—		—		157
Mortgage- and asset-backed securities	—		69		—		—		69
Corporate bonds	—		394		—		—		394
Pooled funds	—		173		—		—		173
Cash equivalents and other	—		50		—		—		50
Real estate investments	103		—		—		421		524
Private equity	—		—		—		220		220
Total	$	1,080	$	1,422	$	—	$	641	$	3,143



*	Level 1 securities consist of actively traded stocks while Level 2 securities consist of pooled funds. Management believes that the portfolio is well-diversified with no significant concentrations of risk.



	Fair Value Measurements Using
	Quoted Prices in Active Markets for Identical Assets			Significant Other Observable Inputs		Significant Unobservable Inputs		Net Asset Value as a Practical Expedient
As of December 31, 2014:	(Level 1)			(Level 2)		(Level 3)		(NAV)		Total
	(in millions)
Assets:
Domestic equity*	$	595		$	246	$	—	$	—	$	841
International equity*	373			344		—		—		717
Fixed income:
U.S. Treasury, government, and agency bonds	—			244		—		—		244
Mortgage- and asset-backed securities	—			66		—		—		66
Corporate bonds	—			398		—		—		398
Pooled funds	—			179		—		—		179
Cash equivalents and other	1			230		—		—		231
Real estate investments	102			—		—		391		493
Private equity	—			—		—		199		199
Total	$	1,071		$	1,707	$	—	$	590	$	3,368
Liabilities:
Derivatives	$	(1	)	$	—	$	—	$	—	$	(1	)
Total	$	1,070		$	1,707	$	—	$	590	$	3,367



*	Level 1 securities consist of actively traded stocks while Level 2 securities consist of pooled funds. Management believes that the portfolio is well-diversified with no significant concentrations of risk.

Gulf Power [Member]

Weighted average rates assumed in actuarial calculations used to determine both benefit obligations as of measurement date and net periodic costs for pension and other postretirement benefit plans



Assumptions used to determine net periodic costs:	2015		2014		2013
Pension plans
Discount rate – interest costs	4.18	%	5.02	%	4.27	%
Discount rate – service costs	4.48		5.02		4.27
Expected long-term return on plan assets	8.20		8.20		8.20
Annual salary increase	3.59		3.59		3.59
Other postretirement benefit plans
Discount rate – interest costs	4.04	%	4.86	%	4.06	%
Discount rate – service costs	4.38		4.86		4.06
Expected long-term return on plan assets	8.07		8.08		8.04
Annual salary increase	3.59		3.59		3.59



Assumptions used to determine benefit obligations:	2015		2014
Pension plans
Discount rate	4.71	%	4.18	%
Annual salary increase	4.46		3.59
Other postretirement benefit plans
Discount rate	4.51	%	4.04	%
Annual salary increase	4.46		3.59

Effect of 1% annual increase or decrease in assumed medical care cost on APBO and service and interest cost components

The weighted average medical care cost trend rates used in measuring the APBO as of December 31, 2015 were as follows:



	Initial Cost Trend Rate		Ultimate Cost Trend Rate		Year That Ultimate Rate is Reached
Pre-65	6.50	%	4.50	%	2024
Post-65 medical	5.50		4.50		2024
Post-65 prescription	10.00		4.50		2025

An annual increase or decrease in the assumed medical care cost trend rate of 1% would affect the APBO and the service and interest cost components at December 31, 2015 as follows:



	1 Percent Increase		1 Percent Decrease
	(in millions)
Benefit obligation	$	4	$	(3	)
Service and interest costs	—		—

Changes in projected benefit obligations and fair value of plan assets

Changes in the projected benefit obligations and the fair value of plan assets during the plan years ended December 31, 2015 and 2014 were as follows:



	2015			2014
	(in millions)
Change in benefit obligation
Benefit obligation at beginning of year	$	491		$	395
Service cost	12			10
Interest cost	20			19
Benefits paid	(20		)	(16		)
Actuarial loss (gain)	(23		)	83
Balance at end of year	480			491
Change in plan assets
Fair value of plan assets at beginning of year	435			386
Actual return on plan assets	4			34
Employer contributions	1			31
Benefits paid	(20		)	(16		)
Fair value of plan assets at end of year	420			435
Accrued liability	$	(60	)	$	(56	)



	2015		2014		Estimated Amortization in 2016
	(in millions)
Prior service cost	$	2	$	3	$	1
Net loss	140		143		6
Regulatory assets	$	142	$	146

Components of other comprehensive income along with changes in balances of regulatory assets and regulatory liabilities related to defined benefit pension plans

The changes in the balance of regulatory assets related to the defined benefit pension plans for the years ended December 31, 2015 and 2014 are presented in the following table:



	2015			2014
	(in millions)
Regulatory assets:
Beginning balance	$	146		$	75
Net (gain) loss	6			77
Reclassification adjustments:
Amortization of prior service costs	(1		)	(1		)
Amortization of net gain (loss)	(9		)	(5		)
Total reclassification adjustments	(10		)	(6		)
Total change	(4		)	71
Ending balance	$	142		$	146

Changes in the accumulated postretirement benefit obligations (APBO) and in fair value of plan assets

At December 31, 2015, estimated benefit payments were as follows:



	Benefit Payments
	(in millions)
2016	$	19
2017	20
2018	21
2019	22
2020	24
2021 to 2025	139

Changes in the APBO and in the fair value of plan assets during the plan years ended December 31, 2015 and 2014 were as follows:



	2015			2014
	(in millions)
Change in benefit obligation
Benefit obligation at beginning of year	$	78		$	69
Service cost	1			1
Interest cost	3			3
Benefits paid	(4		)	(4		)
Actuarial loss (gain)	(1		)	11
Plan amendment	4			(2		)
Retiree drug subsidy	—			—
Balance at end of year	81			78
Change in plan assets
Fair value of plan assets at beginning of year	18			17
Actual return on plan assets	—			2
Employer contributions	3			3
Benefits paid	(4		)	(4		)
Fair value of plan assets at end of year	17			18
Accrued liability	$	(64	)	$	(60	)

Amounts included in accumulated other comprehensive income and regulatory assets related to other postretirement benefit plans



	2015		2014			Estimated Amortization in 2016
	(in millions)
Prior service cost	$	—	$	(2	)	$	—
Net loss	5		4			—
Net regulatory assets (liabilities)	$	5	$	2

Components of other comprehensive income along with changes in balance of regulatory assets related to other postretirement benefit plans



	2015		2014
	(in millions)
Net regulatory assets (liabilities):
Beginning balance	$	2	$	(7	)
Net (gain) loss	1		11
Change in prior service costs	2		(2		)
Reclassification adjustments:
Amortization of prior service costs	—		—
Amortization of net gain (loss)	—		—
Total reclassification adjustments	—		—
Total change	3		9
Ending balance	$	5	$	2

Summary of estimation of future benefit payments and subsidy receipts based on assumptions used to measure accumulated benefit obligation for postretirement plans



	Benefit Payments		Subsidy Receipts			Total
	(in millions)
2016	$	5	$	—		$	5
2017	5		—			5
2018	6		—			6
2019	6		(1		)	5
2020	6		(1		)	5
2021 to 2025	29		(3		)	26

Composition of benefit plan assets along with targeted mix of assets

The composition of the Company's pension plan and other postretirement benefit plan assets as of December 31, 2015 and 2014, along with the targeted mix of assets for each plan, is presented below:



	Target		2015		2014
Pension plan assets:
Domestic equity	26	%	30	%	30	%
International equity	25		23		23
Fixed income	23		23		27
Special situations	3		2		1
Real estate investments	14		16		14
Private equity	9		6		5
Total	100	%	100	%	100	%
Other postretirement benefit plan assets:
Domestic equity	25	%	29	%	29	%
International equity	24		22		22
Domestic fixed income	25		25		29
Special situations	3		2		1
Real estate investments	14		16		14
Private equity	9		6		5
Total	100	%	100	%	100	%

Gulf Power [Member] | Pension Plans [Member]

Amounts recognized in balance sheets related to benefit plans

Amounts recognized in the balance sheets at December 31, 2015 and 2014 related to the Company's pension plans consist of the following:



	2015			2014
	(in millions)
Other regulatory assets, deferred	$	142		$	146
Current liabilities, other	(1		)	(1		)
Employee benefit obligations	(59		)	(55		)

Components of net periodic pension cost were as follows:



	2015			2014			2013
	(in millions)
Service cost	$	12		$	10		$	11
Interest cost	20			19			17
Expected return on plan assets	(32		)	(28		)	(26		)
Recognized net loss	9			5			9
Net amortization	1			1			1
Net periodic pension cost	$	10		$	7		$	12

Gulf Power [Member] | Other Postretirement Benefits [Member]



	Fair Value Measurements Using
	Quoted Prices in Active Markets for Identical Assets		Significant Other Observable Inputs		Significant Unobservable Inputs		Net Asset Value as a Practical Expedient
As of December 31, 2015:	(Level 1)		(Level 2)		(Level 3)		(NAV)		Total
	(in millions)
Assets:
Domestic equity*	$	73	$	31	$	—	$	—	$	104
International equity*	54		45		—		—		99
Fixed income:
U.S. Treasury, government, and agency bonds	—		21		—		—		21
Mortgage- and asset-backed securities	—		9		—		—		9
Corporate bonds	—		51		—		—		51
Pooled funds	—		23		—		—		23
Cash equivalents and other	—		7		—		—		7
Real estate investments	14		—		—		55		69
Private equity	—		—		—		29		29
Total	$	141	$	187	$	—	$	84	$	412



*	Level 1 securities consist of actively traded stocks while Level 2 securities consist of pooled funds. Management believes that the portfolio is well-diversified with no significant concentrations of risk.



	Fair Value Measurements Using
	Quoted Prices in Active Markets for Identical Assets		Significant Other Observable Inputs		Significant Unobservable Inputs		Net Asset Value as a Practical Expedient
As of December 31, 2014:	(Level 1)		(Level 2)		(Level 3)		(NAV)		Total
	(in millions)
Assets:
Domestic equity*	$	77	$	32	$	—	$	—	$	109
International equity*	48		44		—		—		92
Fixed income:
U.S. Treasury, government, and agency bonds	—		31		—		—		31
Mortgage- and asset-backed securities	—		8		—		—		8
Corporate bonds	—		51		—		—		51
Pooled funds	—		23		—		—		23
Cash equivalents and other	—		30		—		—		30
Real estate investments	13		—		—		50		63
Private equity	—		—		—		26		26
Total	$	138	$	219	$	—	$	76	$	433



*	Level 1 securities consist of actively traded stocks while Level 2 securities consist of pooled funds. Management believes that the portfolio is well-diversified with no significant concentrations of risk.

Amounts recognized in balance sheets related to benefit plans

Amounts recognized in the balance sheets at December 31, 2015 and 2014 related to the Company's other postretirement benefit plans consist of the following:



	2015			2014
	(in millions)
Other regulatory assets, deferred	$	10		$	6
Current liabilities, other	(1		)	(1		)
Other regulatory liabilities, deferred	(5		)	(4		)
Employee benefit obligations	(63		)	(59		)

Components of the other postretirement benefit plans' net periodic cost were as follows:



	2015			2014			2013
	(in millions)
Service cost	$	1		$	1		$	1
Interest cost	3			3			3
Expected return on plan assets	(1		)	(1		)	(1		)
Net amortization	—			—			—
Net periodic postretirement benefit cost	$	3		$	3		$	3

Mississippi Power [Member]



	Fair Value Measurements Using
	Quoted Prices in Active Markets for Identical Assets		Significant Other Observable Inputs		Significant Unobservable Inputs		Net Asset Value as a Practical Expedient
As of December 31, 2015:	(Level 1)		(Level 2)		(Level 3)		(NAV)		Total
	(in millions)
Assets:
Domestic equity*	$	3	$	1	$	—	$	—	$	4
International equity*	2		2		—		—		4
Fixed income:
U.S. Treasury, government, and agency bonds	—		1		—		—		1
Mortgage- and asset-backed securities	—		—		—		—		—
Corporate bonds	—		2		—		—		2
Pooled funds	—		1		—		—		1
Cash equivalents and other	1		—		—		—		1
Real estate investments	1		—		—		2		3
Private equity	—		—		—		1		1
Total	$	7	$	7	$	—	$	3	$	17



*	Level 1 securities consist of actively traded stocks while Level 2 securities consist of pooled funds. Management believes that the portfolio is well-diversified with no significant concentrations of risk.



	Fair Value Measurements Using
	Quoted Prices in Active Markets for Identical Assets		Significant Other Observable Inputs		Significant Unobservable Inputs		Net Asset Value as a Practical Expedient
As of December 31, 2014:	(Level 1)		(Level 2)		(Level 3)		(NAV)		Total
	(in millions)
Assets:
Domestic equity*	$	3	$	1	$	—	$	—	$	4
International equity*	2		2		—		—		4
Fixed income:
U.S. Treasury, government, and agency bonds	—		1		—		—		1
Mortgage- and asset-backed securities	—		1		—		—		1
Corporate bonds	—		2		—		—		2
Pooled funds	—		1		—		—		1
Cash equivalents and other	—		1		—		—		1
Real estate investments	1		—		—		2		3
Private equity	—		—		—		1		1
Total	$	6	$	9	$	—	$	3	$	18



*	Level 1 securities consist of actively traded stocks while Level 2 securities consist of pooled funds. Management believes that the portfolio is well-diversified with no significant concentrations of risk.

Weighted average rates assumed in actuarial calculations used to determine both benefit obligations as of measurement date and net periodic costs for pension and other postretirement benefit plans



Assumptions used to determine net periodic costs:	2015		2014		2013
Pension plans
Discount rate – interest costs	4.17	%	5.01	%	4.26	%
Discount rate – service costs	4.49		5.01		4.26
Expected long-term return on plan assets	8.20		8.20		8.20
Annual salary increase	3.59		3.59		3.59
Other postretirement benefit plans
Discount rate – interest costs	4.03	%	4.85	%	4.04	%
Discount rate – service costs	4.38		4.85		4.04
Expected long-term return on plan assets	7.23		7.30		7.04
Annual salary increase	3.59		3.59		3.59



Assumptions used to determine benefit obligations:	2015		2014
Pension plans
Discount rate	4.69	%	4.17	%
Annual salary increase	4.46		3.59
Other postretirement benefit plans
Discount rate	4.47	%	4.03	%
Annual salary increase	4.46		3.59

Effect of 1% annual increase or decrease in assumed medical care cost on APBO and service and interest cost components

The weighted average medical care cost trend rates used in measuring the APBO as of December 31, 2015 were as follows:



	Initial Cost Trend Rate		Ultimate Cost Trend Rate		Year That Ultimate Rate is Reached
Pre-65	6.50	%	4.50	%	2024
Post-65 medical	5.50		4.50		2024
Post-65 prescription	10.00		4.50		2025

An annual increase or decrease in the assumed medical care cost trend rate of 1% would affect the APBO and the service and interest cost components at December 31, 2015 as follows:



	1 Percent Increase		1 Percent Decrease
	(in millions)
Benefit obligation	$	5	$	(5	)
Service and interest costs	—		—

Changes in projected benefit obligations and fair value of plan assets

Changes in the projected benefit obligations and the fair value of plan assets during the plan years ended December 31, 2015 and 2014 were as follows:



	2015			2014
	(in millions)
Change in benefit obligation
Benefit obligation at beginning of year	$	513		$	409
Service cost	13			10
Interest cost	21			20
Benefits paid	(22		)	(17		)
Actuarial loss (gain)	(25		)	91
Balance at end of year	500			513
Change in plan assets
Fair value of plan assets at beginning of year	446			387
Actual return on plan assets	4			40
Employer contributions	2			36
Benefits paid	(22		)	(17		)
Fair value of plan assets at end of year	430			446
Accrued liability	$	(70	)	$	(67	)

Amounts recognized in balance sheets related to benefit plans

Amounts recognized in the balance sheets at December 31, 2015 and 2014 related to the Company's other postretirement benefit plans consist of the following:



	2015			2014
	(in millions)
Other regulatory assets, deferred	$	21		$	18
Other regulatory liabilities, deferred	(3		)	(2		)
Employee benefit obligations	(74		)	(72		)

Components of other comprehensive income along with changes in balances of regulatory assets and regulatory liabilities related to defined benefit pension plans

The changes in the balance of regulatory assets related to the defined benefit pension plans for the years ended December 31, 2015 and 2014 are presented in the following table:



	2015			2014
	(in millions)
Regulatory assets:
Beginning balance	$	151		$	78
Net (gain) loss	4			79
Reclassification adjustments:
Amortization of prior service costs	(1		)	(1		)
Amortization of net gain (loss)	(10		)	(5		)
Total reclassification adjustments	(11		)	(6		)
Total change	(7		)	73
Ending balance	$	144		$	151

Changes in the accumulated postretirement benefit obligations (APBO) and in fair value of plan assets

At December 31, 2015, estimated benefit payments were as follows:



	Benefit Payments
	(in millions)
2016	$	20
2017	21
2018	22
2019	24
2020	25
2021 to 2025	146

Changes in the APBO and in the fair value of plan assets during the plan years ended December 31, 2015 and 2014 were as follows:



	2015			2014
	(in millions)
Change in benefit obligation
Benefit obligation at beginning of year	$	96		$	81
Service cost	1			1
Interest cost	4			4
Benefits paid	(5		)	(5		)
Actuarial loss (gain)	(1		)	14
Plan amendment	1			—
Retiree drug subsidy	1			1
Balance at end of year	97			96
Change in plan assets
Fair value of plan assets at beginning of year	24			23
Actual return on plan assets	—			2
Employer contributions	3			3
Benefits paid	(4		)	(4		)
Fair value of plan assets at end of year	23			24
Accrued liability	$	(74	)	$	(72	)

Components of other comprehensive income along with changes in balance of regulatory assets related to other postretirement benefit plans



	2015			2014
	(in millions)
Net regulatory assets (liabilities):
Beginning balance	$	16		$	2
Net (gain) loss	—			14
Change in prior service costs	3			—
Reclassification adjustments:
Amortization of net gain (loss)	(1		)	—
Total reclassification adjustments	(1		)	—
Total change	2			14
Ending balance	$	18		$	16

Summary of estimation of future benefit payments and subsidy receipts based on assumptions used to measure accumulated benefit obligation for postretirement plans

Estimated benefit payments are reduced by drug subsidy receipts expected as a result of the Medicare Prescription Drug, Improvement, and Modernization Act of 2003 as follows:



	Benefit Payments		Subsidy Receipts			Total
	(in millions)
2016	$	6	$	—		$	6
2017	6		(1		)	5
2018	6		(1		)	5
2019	7		(1		)	6
2020	7		(1		)	6
2021 to 2025	36		(2		)	34

Composition of benefit plan assets along with targeted mix of assets

The composition of the Company's pension plan and other postretirement benefit plan assets as of December 31, 2015 and 2014, along with the targeted mix of assets for each plan, is presented below:



	Target		2015		2014
Pension plan assets:
Domestic equity	26	%	30	%	30	%
International equity	25		23		23
Fixed income	23		23		27
Special situations	3		2		1
Real estate investments	14		16		14
Private equity	9		6		5
Total	100	%	100	%	100	%
Other postretirement benefit plan assets:
Domestic equity	21	%	24	%	24	%
International equity	20		18		19
Domestic fixed income	38		38		41
Special situations	3		2		1
Real estate investments	11		13		11
Private equity	7		5		4
Total	100	%	100	%	100	%

Mississippi Power [Member] | Pension Plans [Member]

Amounts recognized in balance sheets related to benefit plans

Amounts recognized in the balance sheets at December 31, 2015 and 2014 related to the Company's pension plans consist of the following:



	2015			2014
	(in millions)
Other regulatory assets, deferred	$	144		$	151
Other current liabilities	(3		)	(2		)
Employee benefit obligations	(67		)	(65		)



	2015		2014		Estimated Amortization in 2016
	(in millions)
Prior service cost	$	2	$	3	$	1
Net loss	142		148		7
Regulatory assets	$	144	$	151

Components of net periodic pension cost were as follows:



	2015			2014			2013
	(in millions)
Service cost	$	13		$	10		$	11
Interest cost	21			20			18
Expected return on plan assets	(33		)	(29		)	(27		)
Recognized net loss	10			5			10
Net amortization	1			1			1
Net periodic pension cost	$	12		$	7		$	13

Mississippi Power [Member] | Other Postretirement Benefits [Member]



	Fair Value Measurements Using
	Quoted Prices in Active Markets for Identical Assets		Significant Other Observable Inputs		Significant Unobservable Inputs		Net Asset Value as a Practical Expedient
As of December 31, 2015:	(Level 1)		(Level 2)		(Level 3)		(NAV)		Total
	(in millions)
Assets:
Domestic equity*	$	76	$	32	$	—	$	—	$	108
International equity*	55		46		—		—		101
Fixed income:
U.S. Treasury, government, and agency bonds	—		21		—		—		21
Mortgage- and asset-backed securities	—		9		—		—		9
Corporate bonds	—		53		—		—		53
Pooled funds	—		23		—		—		23
Cash equivalents and other	—		7		—		—		7
Real estate investments	14		—		—		57		71
Private equity	—		—		—		30		30
Total	$	145	$	191	$	—	$	87	$	423



*	Level 1 securities consist of actively traded stocks while Level 2 securities consist of pooled funds. Management believes that the portfolio is well-diversified with no significant concentrations of risk.



	Fair Value Measurements Using
	Quoted Prices in Active Markets for Identical Assets		Significant Other Observable Inputs		Significant Unobservable Inputs		Net Asset Value as a Practical Expedient
As of December 31, 2014:	(Level 1)		(Level 2)		(Level 3)		(NAV)		Total
	(in millions)
Assets:
Domestic equity*	$	78	$	32	$	—	$	—	$	110
International equity*	49		45		—		—		94
Fixed income:
U.S. Treasury, government, and agency bonds	—		32		—		—		32
Mortgage- and asset-backed securities	—		9		—		—		9
Corporate bonds	—		53		—		—		53
Pooled funds	—		24		—		—		24
Cash equivalents and other	—		30		—		—		30
Real estate investments	14		—		—		51		65
Private equity	—		—		—		26		26
Total	$	141	$	225	$	—	$	77	$	443



*	Level 1 securities consist of actively traded stocks while Level 2 securities consist of pooled funds. Management believes that the portfolio is well-diversified with no significant concentrations of risk.



	2015			2014			Estimated Amortization in 2016
	(in millions)
Prior service cost	$	—		$	(2	)	$	—
Net (gain) loss	(18		)	18			1
Net regulatory assets	$	(18	)	$	16

Components of the other postretirement benefit plans' net periodic cost were as follows:



	2015			2014			2013
	(in millions)
Service cost	$	1		$	1		$	1
Interest cost	4			4			4
Expected return on plan assets	(2		)	(2		)	(1		)
Net amortization	1			—			—
Net periodic postretirement benefit cost	$	4		$	3		$	4