General and Summary of Significant Accounting Policies New Accounting Pronouncements Adopted (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	Jan. 01, 2019	Jan. 01, 2018	Dec. 31, 2015
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Operating Lease, Right-of-Use Asset																			$ 300
Revenues	$ 2,622		$ 2,837		$ 2,537		$ 2,740		$ 2,643		$ 2,693	$ 2,613		$ 2,581		$ 10,736	$ 10,530	$ 10,281
Cost of Goods and Services Sold																(8,163)	(8,065)	(7,898)
Gross Profit	646		671		600		656		645		640	623		557		2,573	2,465	2,383
Interest income																310	244	245
Other Income																72	120	64
Other Assets, Current	807								630							807	630			$ 691
Deferred Tax Assets, Net of Valuation Allowance, Noncurrent	97								130							97	130			106
Service Concession Assets	0								1,360							0	1,360			0
Notes, Loans and Financing Receivable, Gross, Noncurrent	1,423								0							1,423	0			1,490
Assets	32,521								33,112							32,521	33,112	36,124
Retained Earnings (Accumulated Deficit)	(1,005)								(2,276)							(1,005)	(2,276)			(2,209)
Cash and Cash Equivalents, at Carrying Value	1,166								949							1,166	949
Restricted Cash and Cash Equivalents, Current	370								274							370	274
Other Comprehensive Income (Loss), Effect of Change in Accounting Principle, Net of Taxes																(151)	919	1,036
Debt service reserves and other deposits	467								565							467	565
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents	2,003								1,788							2,003	1,788	1,960			$ 1,951
Accumulated Other Comprehensive Income (Loss), Net of Tax	(2,071)								(1,876)							(2,071)	(1,876)	(2,756)		(1,857)
Stockholders' Equity Attributable to Noncontrolling Interest	2,396								2,380							2,396	2,380			2,461
Liabilities and Equity	32,521								33,112							32,521	33,112
Income (Loss) from Continuing Operations before Equity Method Investments, Income Taxes, Noncontrolling Interest																2,018	771	187
Income (Loss) from Continuing Operations, net of Tax	155	[1]	192	[1]	224	[1]	778	[1]	(622)	[2]	235	142	[2]	97	[2]	1,349	(148)	191
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest	181		191		416		777		(1,286)		261	150		98		1,565	(777)	(777)
NET INCOME (LOSS) ATTRIBUTABLE TO THE AES CORPORATION	128		$ 101		$ 290		$ 684		(1,342)		$ 152	$ 53		$ (24)		1,203	$ (1,161)	$ (1,130)
Balance Without the Adoption of ASC 606 [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Revenues																10,800
Cost of Goods and Services Sold																(8,207)
Gross Profit																2,593
Interest income																252
Other Income																70
Other Assets, Current	741															741
Deferred Tax Assets, Net of Valuation Allowance, Noncurrent	122															122
Service Concession Assets	1,261															1,261
Notes, Loans and Financing Receivable, Gross, Noncurrent	0															0
Assets	32,318															32,318
Retained Earnings (Accumulated Deficit)	(1,112)															(1,112)
Accumulated Other Comprehensive Income (Loss), Net of Tax	(2,088)															(2,088)
Stockholders' Equity Attributable to Noncontrolling Interest	2,317															2,317
Liabilities and Equity	32,318															32,318
Income (Loss) from Continuing Operations before Equity Method Investments, Income Taxes, Noncontrolling Interest																1,978
Income (Loss) from Continuing Operations, net of Tax																1,309
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest																1,525
NET INCOME (LOSS) ATTRIBUTABLE TO THE AES CORPORATION																1,163
ASC 606 Impact [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Revenues																(64)
Cost of Goods and Services Sold																44
Gross Profit																(20)
Interest income																58
Other Income																2
Other Assets, Current	66															66				61
Deferred Tax Assets, Net of Valuation Allowance, Noncurrent	(25)															(25)				(24)
Service Concession Assets	(1,261)															(1,261)				(1,360)
Notes, Loans and Financing Receivable, Gross, Noncurrent	1,423															1,423				1,490
Assets	203															203
Retained Earnings (Accumulated Deficit)	107															107				67
Accumulated Other Comprehensive Income (Loss), Net of Tax	17															17				19
Stockholders' Equity Attributable to Noncontrolling Interest	79															79				$ 81
Liabilities and Equity	$ 203															203
Income (Loss) from Continuing Operations before Equity Method Investments, Income Taxes, Noncontrolling Interest																40
Income (Loss) from Continuing Operations, net of Tax																40
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest																40
NET INCOME (LOSS) ATTRIBUTABLE TO THE AES CORPORATION																$ 40
Other Expense [Member] | Accounting Standards Update 2017-07 [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
New Accounting Pronouncement or Change in Accounting Principle, Description of Prior-period Information Retrospectively Adjusted																	1	3
Inc (Dec) in Cash provided by Operating Actitvities [Domain] | Accounting Standards Update 2016-18 [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
New Accounting Pronouncement or Change in Accounting Principle, Cumulative Effect of Change on Equity or Net Assets									15								$ 15	$ 13
Dec (Inc) In Net Cash Used by Investing Activities [Domain] | Accounting Standards Update 2016-18 [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
New Accounting Pronouncement or Change in Accounting Principle, Cumulative Effect of Change on Equity or Net Assets									150								150	(28)
Dec (Inc) In Net Cash Used by Financing Activities [Domain] | Accounting Standards Update 2016-18 [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
New Accounting Pronouncement or Change in Accounting Principle, Cumulative Effect of Change on Equity or Net Assets									$ 0								$ 0	$ 0

[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).