Schedule I - Condensed Financial Information of Parent (Balance Sheet) (Details) - USD ($)	Dec. 31, 2019	Jan. 01, 2019	Dec. 31, 2018	Jun. 30, 2018	Jan. 01, 2018	Dec. 31, 2017	Dec. 31, 2015
Current Assets:
Cash and cash equivalents	$ 1,029,000,000		$ 1,166,000,000
Restricted cash	336,000,000		370,000,000
Total current assets	5,231,000,000		5,015,000,000
Investment in and advances to subsidiaries and affiliates	966,000,000		1,114,000,000			$ 1,197,000,000
Office Equipment:
Cost	25,383,000,000		25,242,000,000
Accumulated depreciation	(8,505,000,000)		(8,227,000,000)
Property, plant and equipment, net	22,574,000,000		21,396,000,000
Other Assets:
Deferred income taxes	156,000,000		97,000,000		$ 106,000,000	130,000,000
Other assets	1,635,000,000	$ 1,767,000,000	1,514,000,000
Total other assets	5,843,000,000		6,110,000,000
TOTAL ASSETS	33,648,000,000		32,521,000,000			33,112,000,000
Current Liabilities:
Accounts payable	1,311,000,000		1,329,000,000
Accrued and other liabilities	1,021,000,000	989,000,000	962,000,000
Total current liabilities	5,096,000,000		4,399,000,000
Long-term Liabilities:
Other long-term liabilities	2,917,000,000	$ 2,949,000,000	2,723,000,000
Total noncurrent liabilities	22,435,000,000		21,639,000,000
Stockholders' equity:
Common stock	8,000,000		8,000,000	$ 16.38
Additional paid-in capital	7,776,000,000		8,154,000,000
Accumulated deficit	(692,000,000)		(1,005,000,000)		(2,209,000,000)	(2,276,000,000)
Accumulated other comprehensive loss	(2,229,000,000)		(2,071,000,000)		$ (1,857,000,000)	(1,876,000,000)
Treasury stock	(1,867,000,000)		(1,878,000,000)
Total AES Corporation stockholders’ equity	2,996,000,000		3,208,000,000
TOTAL LIABILITIES AND EQUITY	33,648,000,000		32,521,000,000
Parent Company [Member]
Current Assets:
Cash and cash equivalents	11,000,000		19,000,000			$ 10,000,000	$ 112,000,000
Accounts and notes receivable from subsidiaries	238,000,000		285,000,000
Prepaid expenses and other current assets	35,000,000		31,000,000
Total current assets	284,000,000		335,000,000
Investment in and advances to subsidiaries and affiliates	6,782,000,000		6,834,000,000
Office Equipment:
Cost	27,000,000		27,000,000
Accumulated depreciation	(20,000,000)		(19,000,000)
Property, plant and equipment, net	7,000,000		8,000,000
Other Intangible Assets, Net	1,000,000		3,000,000
Other Assets:
Deferred financing costs, net of accumulated amortization of $5 and $4, respectively	5,000,000		4,000,000
Deferred income taxes	14,000,000		24,000,000
Other assets	16,000,000		2,000,000
Total other assets	36,000,000		33,000,000
TOTAL ASSETS	7,109,000,000		7,210,000,000
Current Liabilities:
Accounts payable	20,000,000		15,000,000
Accounts and notes payable to subsidiaries	339,000,000		74,000,000
Accrued and other liabilities	221,000,000		206,000,000
Senior notes payable—current portion	5,000,000		5,000,000
Total current liabilities	585,000,000		300,000,000
Long-term Liabilities:
Senior notes payable	3,391,000,000		3,650,000,000
Accounts and notes payable to subsidiaries	28,000,000		28,000,000
Other long-term liabilities	109,000,000		24,000,000
Total noncurrent liabilities	3,528,000,000		3,702,000,000
Stockholders' equity:
Common stock	8,000,000		8,000,000
Additional paid-in capital	7,776,000,000		8,154,000,000
Accumulated deficit	(692,000,000)		(1,005,000,000)
Accumulated other comprehensive loss	(2,229,000,000)		(2,071,000,000)
Treasury stock	(1,867,000,000)		(1,878,000,000)
Total AES Corporation stockholders’ equity	2,996,000,000		3,208,000,000
TOTAL LIABILITIES AND EQUITY	$ 7,109,000,000		$ 7,210,000,000