Approximate Nameplate Capacity

No definition available.

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- Definition

The contracted life output of the plant.

+ References

No definition available.

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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.

+ References

No definition available.

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- Definition

The parent entity's interest in net assets of the subsidiary, expressed as a percentage.

+ References

No definition available.

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- Definition

Present value of lessee's discounted obligation for lease payments from operating lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 45
-Paragraph 1
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-URI http://asc.fasb.org/extlink&oid=121603541&loc=SL77918627-209977

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- Definition

Amount of lessee's right to use underlying asset under operating lease.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 45
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=121603541&loc=SL77918627-209977

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- Definition

The cash inflow from the capital received in cash from a partner in a partnership during the period.

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 45
-Paragraph 14
-URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3255-108585

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ACQUISITIONS AND DISPOSITIONS - Schedule of Construction Projects (Details) $ in Millions	1 Months Ended	3 Months Ended		12 Months Ended
	May 31, 2020 MW	Jun. 30, 2021 MW	Dec. 31, 2020 MW	Dec. 31, 2018 USD ($)	Jun. 30, 2020 USD ($)	Mar. 31, 2020 MW	Dec. 31, 2019 USD ($)	Oct. 31, 2019
Business Acquisition [Line Items]
Operating lease ROU assets, net \| $					$ 1,776		$ 1,800
SOUTHERN POWER CO
Business Acquisition [Line Items]
Approximate Nameplate Capacity (MW) \| MW						300
Operating lease ROU assets, net \| $					$ 397		$ 369
SOUTHERN POWER CO \| Reading
Business Acquisition [Line Items]
Approximate Nameplate Capacity (MW) \| MW	200
PPA Contract Period	12 years
SOUTHERN POWER CO \| Reading \| Reading
Business Acquisition [Line Items]
Ownership percentage by parent				100.00%
Operating lease ROU assets, net \| $				$ 24
Operating lease obligations \| $				24
Proceeds from tax equity transaction \| $				$ 156
SOUTHERN POWER CO \| Reading \| Reading \| Class B Membership Interest
Business Acquisition [Line Items]
Ownership percentage by parent				100.00%
SOUTHERN POWER CO \| Skookumchuck \| Skookumchuck
Business Acquisition [Line Items]
Ownership percentage by parent								100.00%
SOUTHERN POWER CO \| Scenario, Forecast \| Skookumchuck
Business Acquisition [Line Items]
Approximate Nameplate Capacity (MW) \| MW			136
PPA Contract Period			20 years
SOUTHERN POWER CO \| Scenario, Forecast \| Garland Solar Storage
Business Acquisition [Line Items]
Approximate Nameplate Capacity (MW) \| MW		88
PPA Contract Period		20 years
SOUTHERN POWER CO \| Scenario, Forecast \| Tranquillity Solar Storage
Business Acquisition [Line Items]
Approximate Nameplate Capacity (MW) \| MW		72
PPA Contract Period		20 years