Income Taxes (Schedule Of Effective Income Tax Rate) (Details)	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Entity Information [Line Items]
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent	35.00%	35.00%	35.00%
State income tax, net of federal tax benefit	4.10%	4.10%	4.70%
Amortization of investment tax credits	(0.90%)	0.80%	1.50%
Preferred dividends of subsidiary	0.70%	0.60%	1.30%
Depreciation flow through and amortization	(0.10%)	(0.50%)	(0.30%)
Additional funds used during construction - equity	(4.10%)	(3.80%)	(3.50%)
Manufacturers' Production Deduction (Sec. 199)	(2.50%)	(1.30%)	(0.00%)
Other - net	0.50%	0.90%	(0.20%)
Effective tax rate	31.70%	32.40%	35.90%
Indianapolis Power And Light Company [Member]
Entity Information [Line Items]
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent	35.00%	35.00%	35.00%
State income tax, net of federal tax benefit	4.00%	4.00%	4.40%
Amortization of investment tax credits	0.70%	0.70%	0.80%
Depreciation flow through and amortization	(0.10%)	(0.40%)	(0.20%)
Additional funds used during construction - equity	(3.10%)	(3.20%)	(1.90%)
Manufacturers' Production Deduction (Sec. 199)	(2.40%)	(2.20%)	(1.00%)
Other - net	(0.20%)	(0.80%)	0.10%
Effective tax rate	32.50%	31.70%	35.60%