OTHER INCOME, NET (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Other Income and Expenses [Abstract]
AFUDC-Equity	$ 5.2	$ 2.3	$ 10.2	$ 5.2
Non-service components of net periodic benefit costs	2.0	1.5	4.0	1.6
Earnings from equity method investments	0.7	0.6	1.3	1.1
Interest income	1.2	0.1	1.3	0.6
Other, net - expense		(0.3)
Other, net - income	0.4		0.2	0.0
Other income, net	$ 9.5	$ 4.2	$ 17.0	$ 8.5

Amount of income (loss) for proportionate share of equity method investee's income (loss).

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