Fair Value (Schedule Of Face And Fair Value Of Debt) (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Debt Instrument, Unamortized Discount	$ 6,500	$ 6,700
Face Value	2,678,800	2,678,800
Fair Value	3,031,140	2,804,265
Indianapolis Power And Light Company
Debt Instrument [Line Items]
Debt Instrument, Unamortized Discount	6,156	6,272
Face Value	1,803,800	1,803,800
Fair Value	2,139,758	1,936,916
Fixed Rate [Member]
Debt Instrument [Line Items]
Face Value	2,523,800	2,523,800
Fair Value	2,876,140	2,649,265
Fixed Rate [Member] \| Indianapolis Power And Light Company
Debt Instrument [Line Items]
Face Value	1,713,800	1,713,800
Fair Value	2,049,758	1,846,916
Variable Rate [Member]
Debt Instrument [Line Items]
Face Value	155,000	155,000
Fair Value	155,000	155,000
Variable Rate [Member] \| Indianapolis Power And Light Company
Debt Instrument [Line Items]
Face Value	90,000	90,000
Fair Value	$ 90,000	$ 90,000

Face (par) amount of debt instrument at time of issuance.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=114775744&loc=d3e28551-108399

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition

Fair value portion of debt instrument payable, including, but not limited to, notes payable and loans payable.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 10
-URI http://asc.fasb.org/extlink&oid=109250915&loc=d3e13433-108611

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+ References

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Amount, after accumulated amortization, of debt discount.

+ References

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-Publisher FASB
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