SIGNIFICANT ACCOUNTING POLICIES - PREPAID EXPENSES AND OTHER ASSETS (Details) - USD ($) $ in Millions	Apr. 19, 2024	Dec. 31, 2024	Dec. 31, 2023
Prepaid Expenses and Other Assets:
Prepaid fuel		$ 31.2	$ 22.5
Prepaid insurance and insurance related receivables		19.1	19.3
Prepaid operating expenses		8.8	8.2
Income tax receivables, net		2.0	125.2
Restricted cash - vessel construction obligations			2.3
Other		12.8	11.4
Total		73.9	188.9
Other Long-term Assets
Pension plan assets		49.0	34.8
Vessel and equipment spare parts		15.9	14.2
Insurance related receivables		9.8	10.2
Other		4.9	7.2
Total		$ 79.6	66.4
Income taxes receivable			$ 118.6
Income tax refund	$ 118.6
Interest on income tax refund	$ 10.2