OPERATING REVENUES - OTHER OPERATING REVENUES (Details) - Other operating revenues - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Disaggregation of Operating Revenues
Other operating revenues	$ 28.6	$ 20.0	$ 104.3	$ 49.9
Late payment charges
Disaggregation of Operating Revenues
Other operating revenues	14.1	16.2	28.7	33.4
Alternative revenues
Disaggregation of Operating Revenues
Other operating revenues	12.3	2.1	72.8	13.9
Other
Disaggregation of Operating Revenues
Other operating revenues	$ 2.2	$ 1.7	$ 2.8	$ 2.6