INCOME TAX EXPENSE (Tables)

9 Months Ended

Sep. 30, 2024

Income Tax Disclosure [Abstract]

Schedule of Income Tax Expense

	Quarter Ended		Nine Months Ended
	September 30,		September 30,
	2024	2023	2024	2023
Millions
Current Income Tax Expense
Federal (a)	$1.5	$4.0	$8.3	$12.6
State	0.6	1.1	7.2	6.5
Total Current Income Tax Expense	$2.1	$5.1	$15.5	$19.1
Deferred Income Tax Expense (Benefit)
Federal (b)	$(2.7)	$5.2	$(12.7)	$(10.9)
State	3.6	9.1	6.1	12.5
Investment Tax Credit Amortization	(0.1)	(0.1)	(0.6)	(0.3)
Total Deferred Income Tax Expense (Benefit)	$0.8	$14.2	$(7.2)	$1.3
Total Income Tax Expense	$2.9	$19.3	$8.3	$20.4

(a)For the quarter and nine months ended September 30, 2024 and 2023, the federal current tax expense is partially offset by tax credits.

(b)For the quarter and nine months ended September 30, 2024, the federal deferred income tax benefit is primarily due to tax credits. For the nine months ended September 30, 2023, the federal deferred income tax benefit is primarily due to tax credits, partially offset by deferred partnership income. For quarter ended September 30, 2023, the federal deferred tax expense was due to deferred partnership income, partially offset by tax credits.

Schedule of Reconciliation of Taxes from Federal Statutory Rate to Total Income Tax Expense

In each quarter, the Company updates its estimate of the annual effective tax rate and if the estimated annual effective tax rate changes, the Company would make a cumulative adjustment in that quarter.

	Quarter Ended				Nine Months Ended
Reconciliation of Taxes from Federal Statutory	September 30,				September 30,
Rate to Total Income Tax Expense	2024		2023		2024		2023
Millions
Income Before Income Taxes	$35.6		$88.9		$97.7		$168.3
Statutory Federal Income Tax Rate	21	%	21	%	21	%	21	%
Income Taxes Computed at Statutory Federal Rate	$7.5		$18.7		$20.5		$35.3
Increase (Decrease) in Income Tax Due to:
State Income Taxes – Net of Federal Income Tax Benefit	3.4		8.0		10.5		15.0
Production Tax Credits (a)	(8.3)		(7.7)		(25.0)		(28.3)
Investment Tax Credits (a)	(0.4)		(1.6)		(1.6)		(5.2)
Regulatory Differences – Excess Deferred Tax	(2.0)		(2.3)		(7.7)		(7.5)
Non-Controlling Interest in Subsidiaries	2.4		3.0		7.6		8.9
AFUDC – Equity	(0.4)		—		(1.3)		—
Nondeductible Portion of Transaction Costs	0.7		—		4.0		—
Other	—		1.2		1.3		2.2
Total Income Tax Expense	$2.9		$19.3		$8.3		$20.4

(a)For the quarter and nine months ended September 30, 2024 and 2023, the credits are presented net of any estimated discount on the sale of certain credits.