General and Summary of Significant Accounting Policies New Accounting Pronouncements Adopted (Details) - USD ($) $ in Millions	3 Months Ended														12 Months Ended
	Dec. 31, 2019		Sep. 30, 2019	Jun. 30, 2019		Mar. 31, 2019	Dec. 31, 2018		Sep. 30, 2018		Jun. 30, 2018		Mar. 31, 2018		Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Jan. 01, 2019	Jan. 01, 2018	Dec. 31, 2016
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Financing Receivable, after Allowance for Credit Loss	$ 109						$ 116								$ 109	$ 116
Other Assets, Noncurrent	1,635						1,514								1,635	1,514		$ 1,767
Operating Lease, Right-of-Use Asset	248														248
Revenues	2,431		$ 2,625	$ 2,483		$ 2,650	2,622		$ 2,837		$ 2,537		$ 2,740		10,189	10,736	$ 10,530
Cost of Goods and Services Sold															(7,840)	(8,163)	(8,065)
Gross Profit	560		701	502		586	646		671		600		656		2,349	2,573	2,465
Interest income															318	310	244
Other Income															145	72	120
Other Assets, Current	802						807								802	807	630		$ 691
Deferred Tax Assets, Net of Valuation Allowance, Noncurrent	156						97								156	97	130		106
Service Concession Assets							0									0	1,360		0
Financing Receivable, before Allowance for Credit Loss, Noncurrent	1,351						1,423								1,351	1,423	0		1,490
Assets	33,648						32,521								33,648	32,521	33,112
Retained Earnings (Accumulated Deficit)	(692)						(1,005)								(692)	(1,005)	(2,276)		(2,209)
Cash and Cash Equivalents, at Carrying Value	1,029						1,166								1,029	1,166
Restricted Cash and Cash Equivalents, Current	336						370								336	370
Other Comprehensive Income (Loss), Effect of Change in Accounting Principle, Net of Taxes															(227)	(151)	919
Debt service reserves and other deposits	207						467								207	467
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents	1,572						2,003								1,572	2,003	1,788			$ 1,960
Accumulated Other Comprehensive Income (Loss), Net of Tax	(2,229)						(2,071)								(2,229)	(2,071)	(1,876)		(1,857)
Stockholders' Equity Attributable to Noncontrolling Interest	2,233						2,396								2,233	2,396	2,380		2,461
Liabilities and Equity	33,648						32,521								33,648	32,521
Income (Loss) from Continuing Operations before Equity Method Investments, Income Taxes, Noncontrolling Interest															1,001	2,018	771
Income (Loss) from Continuing Operations, net of Tax	(120)	[1]	298	66	[1]	233	155	[2]	192	[2]	224	[2]	778	[2]	477	1,349	(148)
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest	(120)		298	67		233	181		191		416		777		478	1,565	(777)
NET INCOME (LOSS) ATTRIBUTABLE TO THE AES CORPORATION	(78)		$ 210	$ 17		$ 154	128		$ 101		$ 290		$ 684		303	1,203	(1,161)
Accrued Liabilities, Current	1,021						962								1,021	962		989
Other Liabilities, Noncurrent	2,917						2,723								2,917	2,723		2,949
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	580						578								580	578
Accounting Standards Update 2016-13 [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Accounts Receivable, before Allowance for Credit Loss, Current	1,500														1,500
Financing Receivable, before Allowance for Credit Loss, Noncurrent	1,400														1,400
Accounting Standards Update 2016-02 [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Other Assets, Noncurrent							253									253
Accrued Liabilities, Current							27									27
Other Liabilities, Noncurrent							226									226
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
Financing Receivable, before Allowance for Credit Loss, 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)
Financing Receivable, before Allowance for Credit Loss, 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
Retained Earnings [Member] | Accounting Standards Update 2017-12 [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																		4
Retained Earnings [Member] | Accounting Standard Update 2014-09 [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																		$ 6
Debt Securities [Member] | Accounting Standards Update 2016-13 [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	326														326
ARGENTINA
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Financing Receivable, after Allowance for Credit Loss	64						$ 93								64	93
Revenues															373	$ 487	$ 435
ARGENTINA | Accounting Standards Update 2016-13 [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Financing Receivable, after Allowance for Credit Loss	$ 64														$ 64

[1] 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).

[2] 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 25—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 22—Asset Impairment Expense), other-than-temporary impairment of Guacolda of $144 million in the fourth quarter of 2018 (See Note 8—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 23—Income Taxes).