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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Paragraph 14
-URI http://asc.fasb.org/extlink&oid=123570139&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	7 Months Ended
	Nov. 30, 2021 MW	Dec. 31, 2020	Nov. 30, 2020 USD ($) MW	Jun. 30, 2020 USD ($)	May 31, 2020 MW	Mar. 31, 2022 MW	Mar. 31, 2022 MW	Dec. 31, 2021	Dec. 31, 2019	Dec. 31, 2018
Tranquility Solar Storage
Business Acquisition [Line Items]
Nameplate capacity placed in service (in MWs)	32
Tranquility Solar Storage \| Scenario, Forecast
Business Acquisition [Line Items]
Approximate Nameplate Capacity (MW)						72	72
PPA Contract Period						20 years
Garland Solar Storage \| Scenario, Forecast
Business Acquisition [Line Items]
Approximate Nameplate Capacity (MW)						88	88
PPA Contract Period							20 years
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
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]
Noncontrolling ownership percentage held by parent									100.00%
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]
Noncontrolling ownership percentage held by parent										100.00%
Proceeds from tax equity transaction \| $				$ 156
Reading \| Class B Membership Interest \| Reading
Business Acquisition [Line Items]
Noncontrolling ownership percentage held by parent								100.00%