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Number Of Financial Investors

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Number Of Wind Farms

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This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized.

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Sum of the carrying amounts as of the balance sheet date of all liabilities that are recognized. Liabilities are probable future sacrifices of economic benefits arising from present obligations of an entity to transfer assets or provide services to other entities in the future.

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Percentage investment held by the managing member or general partner of the limited liability company (LLC) or limited partnership (LP).

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

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Portion of equity (net assets) in a variable interest entity (VIE) not attributable, directly or indirectly, to the parent entity. That is, this is the portion of equity in a VIE that is attributable to the noncontrolling interest (previously referred to as minority interest).

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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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CONSOLIDATED ENTITIES AND EQUITY METHOD INVESTMENTS - SPC Noncontrolling Interests and VIEs Narrative (Details) $ in Millions	1 Months Ended		12 Months Ended
	Dec. 31, 2018 USD ($) investor wind_farm	May 31, 2018	Dec. 31, 2020 USD ($)	Dec. 31, 2018 USD ($) investor wind_farm operating_facility	Dec. 31, 2019 USD ($)
Redeemable Noncontrolling Interest [Line Items]
Assets	$ 116,914		$ 122,935	$ 116,914	$ 118,700
Liabilities			90,410		86,650
Equity investments in unconsolidated subsidiaries			1,362		1,303
Southern Power
Redeemable Noncontrolling Interest [Line Items]
Assets			13,235		14,300
Liabilities			6,604		7,678
Number of wind facilities \| operating_facility				8
Equity investments in unconsolidated subsidiaries			$ 19		28
Southern Power \| SP Solar Holdings I, LP
Redeemable Noncontrolling Interest [Line Items]
Sale of equity interest in limited partnership				33.00%
Southern Power \| SP Wind
Redeemable Noncontrolling Interest [Line Items]
Sale of equity interest in limited partnership				100.00%
Wholly Owned Subsidiary Of Southern Power \| Southern Power \| SP Solar Holdings I, LP
Redeemable Noncontrolling Interest [Line Items]
Ownership interest				66.00%
Wholly Owned Subsidiary Of Southern Power \| Southern Power \| SP Wind
Redeemable Noncontrolling Interest [Line Items]
Ownership interest				100.00%
SP Solar Holdings I, LP \| Southern Power
Redeemable Noncontrolling Interest [Line Items]
Distribution made to limited partner, cash distributions paid, percentage			67.00%
SP Solar Holdings I, LP \| Southern Power \| SP Solar Holdings I, LP
Redeemable Noncontrolling Interest [Line Items]
Sale of equity interest in limited partnership		33.00%
SP Solar Holdings I, LP \| Global Atlantic
Redeemable Noncontrolling Interest [Line Items]
Distribution made to limited partner, cash distributions paid, percentage			33.00%
SP Wind
Redeemable Noncontrolling Interest [Line Items]
Number of wind facilities \| wind_farm	8			8
SP Wind \| Southern Power
Redeemable Noncontrolling Interest [Line Items]
Distribution made to limited partner, cash distributions paid, percentage			60.00%
Number of financial investors \| investor				3
SP Wind \| Southern Power \| SP Wind
Redeemable Noncontrolling Interest [Line Items]
Number of financial investors \| investor	3
SP Wind \| Financial Investors
Redeemable Noncontrolling Interest [Line Items]
Distribution made to limited partner, cash distributions paid, percentage	40.00%		40.00%
General Partner \| Wholly Owned Subsidiary Of Southern Power \| Southern Power \| SP Solar Holdings I, LP
Redeemable Noncontrolling Interest [Line Items]
Ownership interest				1.00%
Variable Interest Entity, Primary Beneficiary \| SP Solar Holdings I, LP \| Southern Power
Redeemable Noncontrolling Interest [Line Items]
Assets			$ 6,100		6,400
Liabilities			387		381
Noncontrolling interests related to other partners' interest			1,100
Variable Interest Entity, Primary Beneficiary \| SP Wind \| Southern Power
Redeemable Noncontrolling Interest [Line Items]
Assets			2,400		2,500
Liabilities			138		128
Noncontrolling interests related to other partners' interest			43		45
Variable Interest Entity, Primary Beneficiary \| Other Variable Interest Entities \| Southern Power
Redeemable Noncontrolling Interest [Line Items]
Assets			1,100
Liabilities			110		104
Noncontrolling interests related to other partners' interest			$ 454		$ 409