OTHER INCOME, NET (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2026	Sep. 30, 2025	Sep. 30, 2026	Sep. 30, 2025
Other Income and Expenses [Abstract]
AFUDC-Equity	$ 38.0	$ 19.7	$ 119.1	$ 49.7
Interest income	1.0	0.3	2.7	2.6
Non-service components of net periodic benefit costs	(5.4)	(4.4)	(16.1)	(13.9)
Other, net (expense)	(0.6)	(0.1)	(0.8)
Other, net income				0.2
Other income, net	$ 33.0	$ 15.5	$ 104.9	$ 38.6

Amount before accretion (amortization) of purchase discount (premium) of interest income on nonoperating securities.

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