Annual increase or decrease in assumed medical care cost trend rate.

No definition available.

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- Definition

Matching limit of contribution by employer.

+ References

No definition available.

+ Details

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- Definition

Maximum limit of contribution of employees base salary.

+ References

No definition available.

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- Definition

Period over which company has elected to amortize changes in market value of all plan assets.

+ References

No definition available.

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- Definition

Voluntary contribution to pension plan.

+ References

No definition available.

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- Definition

For defined benefit pension plans, the actuarial present value of benefits (whether vested or nonvested) attributed by the pension benefit formula to employee service rendered before a specified date and based on employee service and compensation (if applicable) before that date. The accumulated benefit obligation differs from the projected benefit obligation in that it includes no assumption about future compensation levels. For plans with flat-benefit or nonpay-related pension benefit formulas, the accumulated benefit obligation and the projected benefit obligation are the same.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Accumulated Benefit Obligation

-URI http://asc.fasb.org/extlink&oid=6503844

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (e)

-URI http://asc.fasb.org/extlink&oid=28361610&loc=d3e1928-114920

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- Definition

The interest rate used to adjust for the time value of money.

+ References

+ Details

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- Definition

Expected rate of compensation increases (for pay-related plans).

+ References

+ Details

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- Definition

1) For defined benefit pension plans, the benefit obligation is the projected benefit obligation, which is the actuarial present value as of a date of all benefits attributed by the pension benefit formula to employee service rendered prior to that date. 2) For other postretirement defined benefit plans, the benefit obligation is the accumulated postretirement benefit obligation, which is the actuarial present value of benefits attributed to employee service rendered to a particular date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=28361610&loc=d3e1928-114920

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Projected Benefit Obligation

-URI http://asc.fasb.org/extlink&oid=6522206

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Accumulated Postretirement Benefit Obligation

-URI http://asc.fasb.org/extlink&oid=6503904

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- Definition

The increase in the fair value of plan assets from contributions made by the employer.

+ References

+ Details

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- Definition

The assumed health care cost trend rate for the next year used to measure the expected cost of benefits covered by the plan (gross eligible charges). This is based upon the annual rate of change in the cost of health care benefits currently provided by the postretirement benefit plan, due to factors other than changes in the composition of the plan population by age and dependency status.

+ References

+ Details

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- Definition

Amount of employer's best estimate of contributions expected to be paid to the plan during the next fiscal year beginning after the date of the latest statement of financial position.

+ References

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- Definition

The ultimate trend rate for health care costs.

+ References

+ Details

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- Definition

Year the ultimate health care cost trend rate is expected to be reached, in CCYY format.

+ References

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Retirement Benefits - Textual (Details) (USD $)	12 Months Ended
Retirement Benefits - Textual (Details) (USD $)	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Defined Benefit Plan Disclosure [Line Items]
Annual salary increase on net periodic benefit costs	3.59%	3.59%	3.84%	3.84%
Annual increase or decrease in assumed medical care cost trend rate	1.00%
Total accumulated benefit obligation for the pension plans	$ 8,100,000,000	$ 8,500,000,000
Period over which company has elected to amortize changes in the market value of all plan assets	5 years
Pension Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Expected postretirement trust contributions	0
Discount rate on net periodic benefit costs	5.02%	4.26%	4.98%	5.52%
Projected benefit obligations	8,863,000,000	9,302,000,000	8,079,000,000
Total matching contributions	39,000,000	479,000,000
Other Postretirement Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Expected postretirement trust contributions	13,000,000
Discount rate on net periodic benefit costs	4.85%	4.05%	4.88%	5.40%
Initial Cost Trend Rate	7.00%
Ultimate Cost Trend Rate	5.00%
Year That Ultimate Rate Is Reached	2021
Projected benefit obligations	1,682,000,000	1,872,000,000	1,787,000,000
Total matching contributions	39,000,000	55,000,000
Qualified Pension Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Projected benefit obligations	8,300,000,000
Non Qualified Pension Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Projected benefit obligations	549,000,000
Employee Saving Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Matching limit of contribution by employer	85.00%
Maximum limit of contribution of employees base salary	6.00%
Total matching contributions	84,000,000	82,000,000	78,000,000
Alabama Power [Member]
Defined Benefit Plan Disclosure [Line Items]
Annual salary increase on net periodic benefit costs	3.59%	3.59%	3.84%	3.84%
Annual increase or decrease in assumed medical care cost trend rate	1.00%
Total accumulated benefit obligation for the pension plans	1,900,000,000	2,000,000,000
Period over which company has elected to amortize changes in the market value of all plan assets	5 years
Alabama Power [Member] \| Pension Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Voluntary contribution to pension plan	0
Expected postretirement trust contributions	0
Discount rate on net periodic benefit costs	5.02%	4.27%	4.98%	5.52%
Projected benefit obligations	2,112,000,000	2,218,000,000	1,932,000,000
Total matching contributions	9,000,000	8,000,000
Alabama Power [Member] \| Other Postretirement Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Discount rate on net periodic benefit costs	4.86%	4.06%	4.88%	5.41%
Initial Cost Trend Rate	7.00%
Ultimate Cost Trend Rate	5.00%
Year That Ultimate Rate Is Reached	2021
Projected benefit obligations	431,000,000	490,000,000	470,000,000
Total matching contributions	7,000,000	11,000,000
Alabama Power [Member] \| Qualified Pension Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Projected benefit obligations	2,000,000,000
Alabama Power [Member] \| Non Qualified Pension Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Projected benefit obligations	110,000,000
Alabama Power [Member] \| Employee Saving Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Matching limit of contribution by employer	85.00%
Maximum limit of contribution of employees base salary	6.00%
Total matching contributions	20,000,000	19,000,000	18,000,000
Georgia Power [Member]
Defined Benefit Plan Disclosure [Line Items]
Expected postretirement trust contributions	13,000,000
Annual salary increase on net periodic benefit costs	3.59%	3.59%	3.84%	3.84%
Annual increase or decrease in assumed medical care cost trend rate	1.00%
Period over which company has elected to amortize changes in the market value of all plan assets	5 years
Georgia Power [Member] \| Pension Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Voluntary contribution to pension plan	0
Expected postretirement trust contributions	0
Discount rate on net periodic benefit costs	5.02%	4.27%	4.98%	5.52%
Total accumulated benefit obligation for the pension plans	2,900,000,000	3,100,000,000
Projected benefit obligations	3,116,000,000	3,312,000,000	2,909,000,000
Total matching contributions	12,000,000	11,000,000
Georgia Power [Member] \| Other Postretirement Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Discount rate on net periodic benefit costs	4.85%	4.04%	4.87%	5.40%
Initial Cost Trend Rate	7.00%
Ultimate Cost Trend Rate	5.00%
Year That Ultimate Rate Is Reached	2021
Projected benefit obligations	723,000,000	800,000,000	774,000,000
Total matching contributions	11,000,000	17,000,000
Georgia Power [Member] \| Qualified Pension Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Projected benefit obligations	3,000,000,000
Georgia Power [Member] \| Non Qualified Pension Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Projected benefit obligations	148,000,000
Georgia Power [Member] \| Employee Saving Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Matching limit of contribution by employer	85.00%
Maximum limit of contribution of employees base salary	6.00%
Total matching contributions	24,000,000	24,000,000	24,000,000
Gulf Power [Member]
Defined Benefit Plan Disclosure [Line Items]
Annual salary increase on net periodic benefit costs	3.59%	3.59%	3.84%	3.84%
Annual increase or decrease in assumed medical care cost trend rate	1.00%
Period over which company has elected to amortize changes in the market value of all plan assets	5 years
Gulf Power [Member] \| Pension Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Discount rate on net periodic benefit costs	5.02%	4.27%	4.98%	5.53%
Total accumulated benefit obligation for the pension plans	353,000,000	371,000,000
Projected benefit obligations	395,328,000	413,501,000	352,834,000
Total matching contributions	1,134,000	14,220,000
Gulf Power [Member] \| Other Postretirement Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Expected postretirement trust contributions	0
Discount rate on net periodic benefit costs	4.86%	4.06%	4.88%	5.41%
Initial Cost Trend Rate	7.00%
Ultimate Cost Trend Rate	5.00%
Year That Ultimate Rate Is Reached	2021
Projected benefit obligations	68,579,000	75,395,000	70,923,000
Total matching contributions	2,381,000	2,648,000
Gulf Power [Member] \| Qualified Pension Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Expected postretirement trust contributions	0
Projected benefit obligations	374,000,000
Gulf Power [Member] \| Non Qualified Pension Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Projected benefit obligations	21,000,000
Gulf Power [Member] \| Employee Saving Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Matching limit of contribution by employer	85.00%
Maximum limit of contribution of employees base salary	6.00%
Total matching contributions	4,100,000	4,000,000	3,700,000
Mississippi Power [Member]
Defined Benefit Plan Disclosure [Line Items]
Annual salary increase on net periodic benefit costs	3.59%	3.59%	3.84%	3.84%
Annual increase or decrease in assumed medical care cost trend rate	1.00%
Total accumulated benefit obligation for the pension plans	370,000,000	392,000,000
Period over which company has elected to amortize changes in the market value of all plan assets	5 years
Total matching contributions	4,100,000	3,900,000	3,800,000
Mississippi Power [Member] \| Pension Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Discount rate on net periodic benefit costs	5.01%	4.26%	4.98%	5.51%
Projected benefit obligations	409,395,000	432,553,000	369,680,000
Total matching contributions	2,430,000	44,930,000
Mississippi Power [Member] \| Other Postretirement Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Discount rate on net periodic benefit costs	4.85%	4.04%	4.87%	5.39%
Initial Cost Trend Rate	7.00%
Ultimate Cost Trend Rate	5.00%
Year That Ultimate Rate Is Reached	2021
Projected benefit obligations	80,940,000	91,783,000	87,447,000
Total matching contributions	2,562,000	3,052,000
Mississippi Power [Member] \| Qualified Pension Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Expected postretirement trust contributions	0
Projected benefit obligations	382,000,000
Mississippi Power [Member] \| Non Qualified Pension Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Projected benefit obligations	$ 28,000,000
Mississippi Power [Member] \| Employee Saving Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Matching limit of contribution by employer	85.00%
Maximum limit of contribution of employees base salary	6.00%