Equity (Reclassifications Out of AOCL) (Details) - USD ($) $ in Millions	3 Months Ended													12 Months Ended
	Dec. 31, 2020	Sep. 30, 2020		Jun. 30, 2020		Mar. 31, 2020		Dec. 31, 2019		Sep. 30, 2019	Jun. 30, 2019		Mar. 31, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Gain (Loss) on Disposition of Business														$ (95)	$ 28	$ 984
Impairment expenses														(1,066)	(277)	(355)
Cost of Goods and Services Sold														6,967	7,840	8,163
General and administrative expenses														165	196	192
Other Expenses														(53)	(80)	(58)
Interest expense														(1,038)	(1,050)	(1,056)
Foreign currency transaction gains (losses)														55	(67)	(72)
Income (loss) from continuing operations before taxes and equity in earnings of affiliates														488	1,001	2,018
Income tax expense														216	352	708
Net equity in earnings (losses) of affiliates		$ (112)						$ (175)						(123)	(172)	39
Income (loss) from continuing operations	$ 401	(481)	[1]	$ 0	[1]	$ 229	[1]	(120)	[2]	$ 298	$ 66	[2]	$ 233	149	477	1,349
Discontinued Operation, Income (Loss) from Discontinued Operation During Phase-out Period, Net of Tax														0	0	9
Net gain from disposal of discontinued operations														3	1	225
Net income (loss)	401	(481)		3		229		(120)		298	67		233	152	478	1,565
Less: Net loss (income) attributable to noncontrolling interests and redeemable stock of subsidiaries														(106)	(175)	(364)
Income (Loss) from Discontinued Operations, Net of Tax, Attributable to Noncontrolling Interest														0	0	2
Net income attributable to The AES Corporation	$ 318	$ (333)		$ (83)		$ 144		$ (78)		$ 210	$ 17		$ 154	46	303	1,203
Reclassification out of Accumulated Other Comprehensive Income
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Net income attributable to The AES Corporation														(264)	(86)	(64)
Available-for-Sale securities, net | Reclassification out of Accumulated Other Comprehensive Income
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Gain (Loss) on Disposition of Business														(192)	(23)	19
Net gain from disposal of discontinued operations														0	0	2
Net income attributable to The AES Corporation														(192)	(23)	21
Accumulated Net Gain (Loss) from Cash Flow Hedges Including Portion Attributable to Noncontrolling Interest [Member] | Reclassification out of Accumulated Other Comprehensive Income
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Gain (Loss) on Disposition of Business														0	1	0
Impairment expenses														(10)	0	0
Revenue from Contract with Customer, Excluding Assessed Tax														(1)	(1)	(6)
Cost of Goods and Services Sold														(3)	(12)	(3)
Interest expense														(60)	(26)	(49)
Foreign currency transaction gains (losses)														(7)	(12)	(59)
Income tax expense														17	13	24
Net equity in earnings (losses) of affiliates														(10)	(5)	0
Derivative gains (losses), net | Reclassification out of Accumulated Other Comprehensive Income
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Income (loss) from continuing operations before taxes and equity in earnings of affiliates														(81)	(50)	(117)
Income (loss) from continuing operations														(74)	(42)	(93)
Net income attributable to The AES Corporation														(72)	(36)	(78)
Accumulated Net Gain (Loss) from Cash Flow Hedges Attributable to Noncontrolling Interest [Member] | Reclassification out of Accumulated Other Comprehensive Income
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Less: Net loss (income) attributable to noncontrolling interests and redeemable stock of subsidiaries														2	6	15
Amortization of defined benefit pension actuarial losses, net | Reclassification out of Accumulated Other Comprehensive Income
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Income (loss) from continuing operations before taxes and equity in earnings of affiliates														0	(28)	(6)
Income (loss) from continuing operations														0	(28)	(4)
Net income (loss)														0	(28)	(6)
Net income attributable to The AES Corporation														0	(27)	(7)
Amortization of defined benefit pension actuarial losses, net | Reclassification out of Accumulated Other Comprehensive Income | Regulated Operation [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Cost of Goods and Services Sold														1	0	0
Amortization of defined benefit pension actuarial losses, net | Reclassification out of Accumulated Other Comprehensive Income | Unregulated Operation [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Cost of Goods and Services Sold														(1)	0	0
Accumulated Defined Benefit Plans Adjustment Attributable to Noncontrolling Interest [Member] | Reclassification out of Accumulated Other Comprehensive Income
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Less: Net loss (income) attributable to noncontrolling interests and redeemable stock of subsidiaries														0	1	(1)
Accumulated Defined Benefit Plans Adjustment Including Portion Attributable to Noncontrolling Interest [Member] | Reclassification out of Accumulated Other Comprehensive Income
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Gain (Loss) on Disposition of Business														0	(26)	0
Other Expenses														0	(2)	6
Income tax expense														0	0	(2)
Net gain from disposal of discontinued operations														$ 0	$ 0	$ (2)

[1] Includes pre-tax impairment expense of $849 million in the third quarter of 2020 (See Note 22—Asset Impairment Expense), other-than-temporary impairment of OPGC of $43 million and $158 million in the first and second quarters of 2020, respectively, and net equity in losses of affiliates, primarily at Guacolda, of $112 million in the third quarter of 2020 (See Note 8—Investments in and Advances to Affiliates).

[2] Includes pre-tax impairment expense of $116 million and $69 million in the second and fourth quarters of 2019, respectively (See Note 22—Asset Impairment Expense), other-than-temporary impairment of OPGC of $92 million, and net equity in losses of affiliates, primarily at Guacolda, of $175 million in the fourth quarter of 2019 (See Note 8—Investments in and Advances to Affiliates).