Equity Equity - Net Income (Loss) Attributable to The AES Corporation (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Equity [Abstract]
Net income (loss) attributable to The AES Corporation	$ 318	$ (333)	$ (83)	$ 144	$ (78)	$ 210	$ 17	$ 154	$ 46	$ 303	$ 1,203
Transfers from the noncontrolling interest:
Net transfers (to) from noncontrolling interest									171	(5)	(3)
Change from net income attributable to The AES Corporation and transfers (to) from noncontrolling interests									217	298	1,200
Additional Paid-in Capital [Member]
Transfers from the noncontrolling interest:
Increase (decrease) in The AES Corporation's paid-in capital for sale of subsidiary shares									260	(5)	(3)
Increase (decrease) in The AES Corporation's paid-in-capital for purchase of subsidiary shares									89	0	0
Retained Earnings [Member]
Transfers from the noncontrolling interest:
Increase (decrease) in The AES Corporation's paid-in capital for sale of subsidiary shares									0	$ 0	$ 0
Increase (decrease) in The AES Corporation's paid-in-capital for purchase of subsidiary shares									$ 0