Derivative Instruments and Hedging Activities (Tables)

9 Months Ended

Sep. 30, 2021

Derivative Instruments and Hedging Activities [Abstract]

Schedule of Derivative Instruments, Effect on Other Comprehensive Income (Loss) [Table Text Block]

The following tables provide information on gains or losses recognized in AOCL for the cash flow hedges for the periods indicated:

	Interest Rate Hedges for the Three Months Ended September 30,
$ in thousands (net of tax)	2021		2020
Beginning accumulated derivative loss in AOCL	$	(29,593)	$	(58,745)
Net gains / (losses) associated with current period hedging transactions	898		3,707
Net (gains) / losses reclassified to interest expense, net of tax	1,358		1,344
Ending accumulated derivative loss in AOCL	$	(27,337)	$	(53,694)

Schedule of Derivative Instruments [Table Text Block]

At September 30, 2021, AES Indiana's outstanding derivative instruments were as follows:

Commodity	Accounting Treatment (a)	Unit	Purchases (in thousands)		Sales (in thousands)		Net Purchases/(Sales) (in thousands)
Interest rate hedges	Designated	USD	$	400,000	$	—	$	400,000
FTRs	Not Designated	MWh	9,715		—		9,715
Forward power contracts	Not Designated	MWh	163		—		163

(a)    Refers to whether the derivative instruments have been designated as a cash flow hedge.