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Distance of Furthest Customer from Indianapolis

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Electric generation capability for summer, megawatts

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Electric generation capability for winter, megawatts

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Materials and supplies, average cost.

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Number of Retail Customers

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Number of Generating Stations

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Ownership Interest in Parent Company, Percent

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Ownership Percentage by Parent (Direct)

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Amount of increase (decrease) in the asset retirement obligation from changes in the amount or timing of the estimated cash flows associated with the settlement of the obligation.

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Overview and Summary of Significant Accounting Policies (Details) $ in Thousands	3 Months Ended			6 Months Ended
	Jun. 30, 2019 USD ($)	Mar. 31, 2019 generating_station mi MW	Jun. 30, 2018 USD ($)	Jun. 30, 2019 USD ($)	Jun. 30, 2018 USD ($)	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)
Debt Instrument [Line Items]
Asset Retirement Obligation, Revision of Estimate				$ (7,717)
Accumulated Other Comprehensive Income (Loss), Net of Tax	$ (17,188)			(17,188)		$ 0
Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, Net of Tax	(11,649)		$ 0	(17,188)	$ 0
Inventories	34,278			34,278		32,457
Cash and cash equivalents	11,405			11,405		33,199
Number of customers		500,000
Distance of furthest customer from Indianapolis \| mi		40
Number of generating stations \| generating_station		4
Restricted Cash and Cash Equivalents	400			400		400
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents	11,805		$ 13,544	11,805	$ 13,544	33,599	$ 30,681
Regulatory assets, current	61,974			61,974		67,211
Inventory, Net	$ 96,252			96,252		$ 99,668
Indianapolis Power And Light Company [Member]
Debt Instrument [Line Items]
Electric generation capability for winter, megawatts \| MW		3,705
Electric generation capability for summer, megawatts \| MW		3,560
Aes U.S. Investments [Member]
Debt Instrument [Line Items]
Ownership percentage by parent (percent)		82.35%
CDPQ [Member]
Debt Instrument [Line Items]
Ownership percentage by parent (percent)		17.65%
Ownership interest in parent company (percent)		15.00%
AES U.S. Holdings, LLC [Member]
Debt Instrument [Line Items]
Ownership interest in parent company (percent)		85.00%
Harding Street [Member]
Debt Instrument [Line Items]
Amount of New Operation for Battery Storage Unit, megawatts \| MW		20
Interest Rate Contract [Member]
Debt Instrument [Line Items]
Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, Net of Tax				$ (17,188)