Pension And Other Postretirement Benefits (Schedule Of Expected Benefit Payments) (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012
2013	$ 51,238
2014	34,665
2015	36,274
2016	37,557
2017	38,962
2018 through 2022 (in total)	216,051
Indianapolis Power And Light Company [Member]
2013	51,238
2014	34,665
2015	36,274
2016	37,557
2017	38,962
2018 through 2022 (in total)	$ 216,051

Amount of benefits expected to be paid in the five fiscal years after the fifth fiscal year following the latest fiscal year from a defined benefit plan.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (f)

-URI http://asc.fasb.org/extlink&oid=21915506&loc=d3e1928-114920

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- Definition

Amount of benefits expected to be paid in the next fiscal year following the latest fiscal year from a defined benefit plan.

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Amount of benefits expected to be paid in the fifth fiscal year following the latest fiscal year from a defined benefit plan.

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Amount of benefits expected to be paid in the fourth fiscal year following the latest fiscal year from a defined benefit plan.

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Amount of benefits expected to be paid in the third fiscal year following the latest fiscal year from a defined benefit plan.

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Amount of benefits expected to be paid in the second fiscal year following the latest fiscal year from a defined benefit plan.

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