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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
-Topic 230
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-Section 45
-Paragraph 14
-URI https://asc.fasb.org/extlink&oid=126954810&loc=d3e3255-108585

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ACQUISITIONS AND DISPOSITIONS - Schedule of Construction Projects (Details) - Southern Power $ in Millions	1 Months Ended						5 Months Ended	6 Months Ended	12 Months Ended
	Feb. 28, 2022 MW	Nov. 30, 2021 MW	Dec. 31, 2020	Nov. 30, 2020 USD ($) MW	Jun. 30, 2020 USD ($)	May 31, 2020 MW	Mar. 31, 2022 MW	Feb. 28, 2022 MW	Dec. 31, 2021 MW	Dec. 31, 2022
Tranquility Solar Storage
Business Acquisition [Line Items]
Approximate Nameplate Capacity (MW)							72
Nameplate capacity placed in service (in MWs)		32
Garland Solar Storage
Business Acquisition [Line Items]
Approximate Nameplate Capacity (MW)							72	88
PPA Contract Period							20 years	20 years
Nameplate capacity placed in service (in MWs)	15								73
Glass Sands
Business Acquisition [Line Items]
Approximate Nameplate Capacity (MW)		118
PPA Contract Period		12 years
Skookumchuck
Business Acquisition [Line Items]
Approximate Nameplate Capacity (MW)				136
PPA Contract Period				20 years
Reading
Business Acquisition [Line Items]
Approximate Nameplate Capacity (MW)						200
PPA Contract Period						12 years
Tranquillity Solar Storage
Business Acquisition [Line Items]
Nameplate capacity placed in service (in MWs)									40
Tranquility Solar Storage \| Class B Membership Interest \| Tranquility Solar Storage
Business Acquisition [Line Items]
Noncontrolling ownership percentage sold by parent			100.00%
Garland Solar Storage \| Class B Membership Interest \| Garland Solar Storage
Business Acquisition [Line Items]
Noncontrolling ownership percentage sold by parent			100.00%
Glass Sands \| Glass Sands
Business Acquisition [Line Items]
Noncontrolling ownership percentage held by parent									100.00%
Skookumchuck \| Skookumchuck
Business Acquisition [Line Items]
Proceeds from tax equity transaction \| $				$ 121
Skookumchuck \| Class B Membership Interest \| Skookumchuck
Business Acquisition [Line Items]
Noncontrolling ownership percentage held by parent				100.00%
Reading \| Reading
Business Acquisition [Line Items]
Proceeds from tax equity transaction \| $					$ 156
Reading \| Class B Membership Interest \| Reading
Business Acquisition [Line Items]
Noncontrolling ownership percentage held by parent										100.00%