Financial Statement Presentation New Accounting Pronouncement Adopted (Details) - USD ($)	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	Jan. 01, 2021	Dec. 31, 2020	Jan. 01, 2020	Dec. 31, 2019
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Cash and Cash Equivalents, at Carrying Value	$ 1,886,000,000			$ 1,089,000,000
Restricted Cash and Cash Equivalents, Current	325,000,000			297,000,000
Debt service reserves and other deposits	395,000,000			441,000,000
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents	2,606,000,000	$ 2,210,000,000		1,827,000,000		$ 1,572,000,000
Accounts Receivable, Allowance for Credit Loss, Current	11,000,000			13,000,000
Accounts Receivable, Allowance for Credit Loss, Writeoff	(3,000,000)	(1,000,000)
Financing Receivable, Allowance for Credit Loss	8,000,000			$ 9,000,000
Accounts and Financing Receivable, Allowance for Credit Loss	59,000,000	68,000,000	$ 62,000,000		$ 68,000,000
Financing Receivable, Allowance for Credit Loss, Period Increase (Decrease)	1,000,000	3,000,000
Financing Receivable, Allowance for Credit Loss, Foreign Currency Translation	(1,000,000)	(2,000,000)
Allowance for Doubtful Accounts, Premiums and Other Receivables	5,000,000	15,000,000
Accounts Receivable [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Accounts Receivable, Allowance for Credit Loss, Current	6,000,000	5,000,000	9,000,000		4,000,000
Accounts Receivable, Allowance for Credit Loss, Period Increase (Decrease)	0	2,000,000
Accounts Receivable, Allowance for Credit Loss, Writeoff	(3,000,000)	(1,000,000)
Financing Receivable, Allowance for Credit Loss, Foreign Currency Translation	0	0
Mong Duong Subsidiary [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Financing Receivable, Allowance for Credit Loss	32,000,000
Accounts and Financing Receivable, Allowance for Credit Loss	32,000,000	34,000,000	32,000,000		34,000,000
Financing Receivable, Allowance for Credit Loss, Period Increase (Decrease)	0	0
Financing Receivable, Allowance for Credit Loss, Writeoff	0	0
Financing Receivable, Allowance for Credit Loss, Foreign Currency Translation	0	0
AES Argentina [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Financing Receivable, Allowance for Credit Loss	20,000,000	28,000,000	20,000,000		29,000,000
Financing Receivable, Allowance for Credit Loss, Period Increase (Decrease)	1,000,000	1,000,000
Financing Receivable, Allowance for Credit Loss, Writeoff	0	0
Financing Receivable, Allowance for Credit Loss, Foreign Currency Translation	(1,000,000)	(2,000,000)
Other Entity [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Accounts Receivable, Allowance for Credit Loss, Period Increase (Decrease)	0	0
Accounts Receivable, Allowance for Credit Loss, Writeoff	0	0
Accounts Receivable, Allowance for Credit Loss, Noncurrent	1,000,000	1,000,000	$ 1,000,000		$ 1,000,000
Financing Receivable, Allowance for Credit Loss, Foreign Currency Translation	$ 0	$ 0