Debt - Subsidiary Non-recourse Debt in Default or Accelerated (Details) $ in Millions	Sep. 30, 2018 USD ($)
Nonrecourse Debt Default [Line Items]
Materiality threshold for cash distribution from business to Parent	20.00%
Debt defaults at risk of causing cross default	0
Debt Default Amount	$ 357
Covenant Violation [Member] \| PUERTO RICO
Nonrecourse Debt Default [Line Items]
Net Assets	135
Debt Default Amount	322
Covenant Violation [Member] \| AES llumina [Member]
Nonrecourse Debt Default [Line Items]
Net Assets	17
Debt Default Amount	$ 35

Amount of net assets (liabilities).

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