Condensed Consolidated Statements of Operations - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Revenues	$ 226.4	$ 240.1
OPERATING COSTS AND EXPENSES:
Net purchased power cost	89.7	122.2
Operation and maintenance	60.9	54.0
Depreciation and amortization	22.6	19.8
Taxes other than income taxes	29.2	25.5
Loss on asset disposal	1.3	0.0
Costs and Expenses	203.7	221.5
OPERATING INCOME	22.7	18.6
OTHER INCOME / (EXPENSE), NET:
Interest expense, net	(20.3)	(18.1)
Other income, net	1.8	1.8
Total other expense, net	(18.5)	(16.3)
Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest	4.2	2.3
Income tax expense	1.6	1.1
NET INCOME	2.6	1.2
Subsidiaries [Member]
Revenues	224.3	237.8
OPERATING COSTS AND EXPENSES:
Net purchased power cost	89.5	122.0
Operation and maintenance	60.7	53.2
Depreciation and amortization	22.1	19.4
Taxes other than income taxes	29.2	25.5
Loss on asset disposal	1.1	0.0
Costs and Expenses	202.6	220.1
OPERATING INCOME	21.7	17.7
OTHER INCOME / (EXPENSE), NET:
Interest expense, net	(11.2)	(8.3)
Other income, net	1.2	1.5
Total other expense, net	(10.0)	(6.8)
Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest	11.7	10.9
Income tax expense	2.3	1.3
NET INCOME	$ 9.4	$ 9.6