PENSION AND POST-RETIREMENT PLANS - STATUS (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Pension Benefits
Change in Benefit Obligation:
Benefit obligation at beginning of year	$ 193.1	$ 187.4
Service cost	3.7	3.1	$ 4.8
Interest cost	9.7	10.0	7.0
Actuarial (gain) loss	(1.2)	5.5
Benefits paid, net of subsidies received	(13.1)	(12.9)
Benefit obligation at end of year	192.2	193.1	187.4
Change in Plan Assets:
Balance at the beginning of the period	227.9	206.3
Actual return on plan assets	21.9	25.5
Employer contribution	4.5	9.0	9.0
Benefits paid, net of subsidies received	(13.1)	(12.9)
Balance at the end of the period	241.2	227.9	206.3
Funded Status and Recognized Plan Assets and Benefit Obligations	49.0	34.8
Post-retirement benefits
Change in Benefit Obligation:
Benefit obligation at beginning of year	19.5	15.3
Service cost	0.2	0.2	0.7
Interest cost	1.0	0.8	0.8
Participant contributions	0.6	0.7
Actuarial (gain) loss	(0.6)	4.5
Benefits paid, net of subsidies received	(2.3)	(2.0)
Benefit obligation at end of year	18.4	19.5	$ 15.3
Change in Plan Assets:
Participant contributions	0.6	0.7
Employer contribution	1.7	1.3
Benefits paid, net of subsidies received	(2.3)	(2.0)
Funded Status and Recognized Plan Assets and Benefit Obligations	$ (18.4)	$ (19.5)