Common Stock Fees and Commissions

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- Definition

Number Of Employees Participating in Stock Option and Performance Share Units Program

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- Definition

Share based compensation arrangement by share based payment award number of shares reserved for issuance pursuant to stock based compensation plan.

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No definition available.

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- Definition

Stock issued during period shares company investment plan and employee and director stock plans.

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- Definition

Price of a single share of a number of saleable stocks paid or offered to be paid in a business combination.

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- Definition

The cash inflow from the additional capital contribution to the entity.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Financing Activities
-URI http://asc.fasb.org/extlink&oid=6513228

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
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-URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3255-108585

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- Definition

The total cash inflow associated with the amount received from holders to acquire the entity's shares under incentive and share awards, including stock option exercises. This item inherently excludes any excess tax benefit, which the entity may have realized and reported separately.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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-Section 45
-Paragraph 14
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-Publisher FASB
-Name Accounting Standards Codification
-Glossary Financing Activities
-URI http://asc.fasb.org/extlink&oid=6513228

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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- Definition

The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

Number of new stock issued during the period.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
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-Subparagraph (SX 210.5-02(29))
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Common Stock and Stock Compensation - Textual Stock Issued, Reserved, Employee (Details) $ / shares in Units, shares in Thousands, $ in Millions	1 Months Ended	3 Months Ended	12 Months Ended
	Jan. 31, 2015 USD ($)	Dec. 31, 2016 USD ($) Employee shares	Dec. 31, 2016 USD ($) Employee shares	Dec. 31, 2015 USD ($) shares	Dec. 31, 2014 USD ($) shares	Jul. 01, 2016 $ / shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock issuances \| $			$ 3,758	$ 256	$ 806
Common stock fees and commissions \| $		$ 3
Stock issued employee and director stock plans			20,000
Proceeds from issuance of shares under share-based compensation plans \| $			$ 874
Number of shares reserved for issuance to stock-based compensation plan			94,000
Number of employees participating in stock-based compensation plans \| Employee		5,229	5,229
Common Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock issued, shares			76,140	6,571	15,769
Treasury Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock issued, shares			2,599	(2,599)	4,996
Underwritten Offerings [Member] \| Common Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock issued, shares			50,800
Common stock issuances \| $			$ 2,500
Underwritten Offerings [Member] \| Treasury Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock issued, shares			2,600
At-The-Market [Member] \| Common Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock issued, shares		8,000
Common stock issuances \| $		$ 381
Southern Company Common Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Remaining shares available for awards		14,000	14,000
Alabama Power [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of employees participating in stock-based compensation plans \| Employee		865	865
Georgia Power [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of employees participating in stock-based compensation plans \| Employee		990	990
Gulf Power [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock issuances \| $	$ 20		$ 0	$ 20	$ 50
Number of employees participating in stock-based compensation plans \| Employee		184	184
Gulf Power [Member] \| Common Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock issued, shares				1,000	0
Mississippi Power [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of employees participating in stock-based compensation plans \| Employee		220	220
Southern Company [Member] \| Southern Company Gas [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Business acquisition share price (in dollars per share) \| $ / shares						$ 66