Derivative Instruments and Hedging Activities (Tables)

12 Months Ended

Dec. 31, 2019

Derivative [Line Items]

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

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

	Interest Rate Hedges for the Year Ended December 31, 2019
$ in thousands (net of tax)
Beginning accumulated derivative gain / (loss) in AOCI	$	—
Net losses associated with current period hedging transactions	(19,750		)
Ending accumulated derivative loss in AOCI	$	(19,750	)
Portion expected to be reclassified to earnings in the next twelve months	$	—
Maximum length of time that we are hedging our exposure to variability in future cash flows related to forecasted transactions (in months)	7

Schedule of Derivative Instruments in Statement of Financial Position, Fair Value [Table Text Block]

			December 31,
Commodity	Hedging Designation	Balance sheet classification	2019		2018
Financial transmission rights	Not a Cash Flow Hedge	Prepayments and other current assets	$	864	$	3,099
Interest rate hedges	Cash Flow Hedge	Accrued and other current liabilities	$	26,560	$	—

Schedule of Derivative Instruments [Table Text Block]

At December 31, 2019, IPL'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	5,707		—		5,707

(a)

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

Subsidiaries [Member]

Derivative [Line Items]

Schedule of Derivative Instruments in Statement of Financial Position, Fair Value [Table Text Block]

			December 31,
Commodity	Hedging Designation	Balance sheet classification	2019		2018
Financial transmission rights	Not a Cash Flow Hedge	Prepayments and other current assets	$	864	$	3,099

Schedule of Derivative Instruments [Table Text Block]

At December 31, 2019, IPL's outstanding derivative instruments were as follows:

Commodity	Accounting Treatment (a)	Unit	Purchases (in thousands)	Sales (in thousands)	Net Purchases/(Sales) (in thousands)
FTRs	Not Designated	MWh	5,707	—	5,707

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