Equity (Reclassifications Out of AOCL) (Details) - USD ($) $ in Millions	3 Months Ended															12 Months Ended
	Dec. 31, 2018		Sep. 30, 2018		Jun. 30, 2018		Mar. 31, 2018		Dec. 31, 2017		Sep. 30, 2017	Jun. 30, 2017		Mar. 31, 2017		Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Gain (Loss) on Disposition of Business	$ 128		$ (21)		$ 89		$ 788					$ (48)				$ 984	$ (52)	$ 29
Cost of Goods and Services Sold																8,163	8,065	7,898
General and administrative expenses																192	215	194
Other Expenses																(58)	(58)	(80)
Interest expense																(1,056)	(1,170)	(1,134)
Foreign currency transaction gains																(72)	42	(15)
Income from continuing operations before taxes and equity in earnings of affiliates																2,018	771	187
Income tax expense																(708)	(990)	(32)
Net equity in earnings of affiliates																39	71	36
Income (loss) from continuing operations	155	[1]	192	[1]	224	[1]	778	[1]	$ (622)	[2]	$ 235	142	[2]	$ 97	[2]	1,349	(148)	191
Net loss from disposal and impairments of discontinued operations																225	(611)	(1,119)
Net income (loss)	181		191		416		777		(1,286)		261	150		98		1,565	(777)	(777)
Less: (Income) from continuing operations attributable to noncontrolling interests																364	359	211
Income (Loss) from Discontinued Operations, Net of Tax, Attributable to Noncontrolling Interest																2	(25)	(142)
Net income attributable to The AES Corporation	$ 128		$ 101		$ 290		$ 684		$ (1,342)		$ 152	$ 53		$ (24)		1,203	(1,161)	(1,130)
Reclassification out of Accumulated Other Comprehensive Income
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Net income attributable to The AES Corporation																(64)	(928)	(1,021)
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																19	(188)	0
Net loss from disposal and impairments of discontinued operations																2	(455)	(992)
Net income attributable to The AES Corporation																21	(643)	(992)
Derivative gains (losses), net | Reclassification out of Accumulated Other Comprehensive Income
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax																(6)	25	111
Cost of Goods and Services Sold																(3)	(12)	57
Interest expense																(49)	(79)	(107)
Foreign currency transaction gains																(59)	15	8
Income from continuing operations before taxes and equity in earnings of affiliates																(117)	(51)	(45)
Income tax expense																24	1	8
Income (loss) from continuing operations																(93)	(50)	(37)
Less: (Income) from continuing operations attributable to noncontrolling interests																15	13	9
Net income attributable to The AES Corporation																(78)	(37)	(28)
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]
Cost of Goods and Services Sold																0	1	0
General and administrative expenses																0	(1)	(1)
Other Expenses																(6)	0	(1)
Income from continuing operations before taxes and equity in earnings of affiliates																(6)	0	(2)
Income tax expense																2	0	3
Income (loss) from continuing operations																(4)	0	1
Net loss from disposal and impairments of discontinued operations																(2)	(266)	(11)
Net income (loss)																(6)	(266)	(10)
Less: (Income) from continuing operations attributable to noncontrolling interests																(1)	0	9
Income (Loss) from Discontinued Operations, Net of Tax, Attributable to Noncontrolling Interest																0	18	0
Net income attributable to The AES Corporation																$ (7)	$ (248)	$ (1)

[1] Includes pre-tax gains on sales of business interests of $788 million, $89 million and $128 million, in the first, second and fourth quarters of 2018, respectively, and pre-tax losses of $21 million in the third quarter of 2018 (See Note 23—Held-for-Sale and Dispositions), pre-tax impairment expense of $92 million, $74 million and $42 million, in the second, third and fourth quarters of 2018, respectively (See Note 20—Asset Impairment Expense), other-than-temporary impairment of Guacolda of $144 million in the fourth quarter of 2018 (See Note 7—Investments in and Advances to Affiliates), SAB 118 charges to finalize the provisional estimate of one-time transition tax on foreign earnings of $33 million and $161 million in the third and fourth quarters of 2018, respectively, and a SAB 118 income tax benefit to finalize the provisional estimate of remeasurement of deferred tax assets and liabilities to the lower corporate tax rate of $77 million in the fourth quarter of 2018 (See Note 21—Income Taxes).

[2] Includes provisional tax expense related to a one-time transition tax on foreign earnings of $675 million and the remeasurement of deferred tax assets and liabilities to the lower corporate tax rate of $39 million in the fourth quarter of 2017 (See Note 21—Income Taxes), pre-tax impairment expense of $168 million, $90 million and $277 million, in the first, second and fourth quarters of 2017, respectively (See Note 20—Asset Impairment Expense), and pre-tax losses on sales of business interests of $48 million in second quarter of 2017 (See Note 23—Held-for-Sale and Dispositions).