Approximate Nameplate Capacity

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Noncontrolling Interest, Number Of Operating Facilities Sold

+ References

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- Definition

Number Of Natural Gas Distributions Utilities Sold

+ References

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- Definition

Percentage investment held by members or limited partners of limited liability company (LLC) or limited partnership (LP).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 272
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6373374&loc=d3e70478-108055

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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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- Definition

The number of states the entity operates in as of the balance sheet date.

+ References

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Summary of Significant Accounting Policies - General (Narrative) (Details)			1 Months Ended
	Dec. 12, 2018 operating_facility	May 22, 2018	Jul. 31, 2018 utility	Dec. 31, 2018 state	Nov. 05, 2018 MW
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Number of natural gas distribution utilities sold \| utility			3
Traditional Operating Companies
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Number of states in which entity provides utilities \| state				4
Southern Power
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Number of operating wind facilities \| operating_facility	8
Southern Power \| Disposal Group, Held-for-sale, Not Discontinued Operations \| Mankato
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Expansion currently under construction (mw) \| MW					385
Southern Power \| SP Solar Holdings I, LP
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Sale of equity interest in limited partnership (percent)		33.00%
Southern Company Gas
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Number of states in which entity provides utilities \| state				4
Number of natural gas distribution utilities sold \| utility			3
SP Solar Holdings I, LP \| Southern Power \| SP Solar Holdings I, LP
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Sale of equity interest in limited partnership (percent)		33.00%