SIGNIFICANT ACCOUNTING POLICIES - PREPAID EXPENSES AND OTHER ASSETS (Details) - USD ($) $ in Millions	Dec. 31, 2025	Dec. 31, 2024
Prepaid Expenses and Other Assets:
Vessel fuel	$ 25.3	$ 31.2
Prepaid insurance and insurance related receivables	21.9	19.1
Prepaid operating expenses	11.6	8.8
Other prepaid expenses	11.1	9.9
Other assets	3.3	4.9
Total	73.2	73.9
Other Long-term Assets:
Pension plan assets	59.8	49.0
Vessel and equipment spare parts	19.8	15.9
Insurance related receivables	6.2	9.8
Other	10.9	4.9
Total	$ 96.7	$ 79.6