INVESTMENT IN SSAT (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2026	Sep. 30, 2025	Sep. 30, 2026	Sep. 30, 2025	Dec. 31, 2025
Investments in affiliates
Investment in SSAT	$ 113.7		$ 113.7		$ 96.2
Operating lease right-of-use assets	364.4		364.4		369.6
Long-term operating lease liabilities	248.1		248.1		246.8
Financial information for equity method investment
Current assets	686.7		686.7		471.9
Non-current assets	4,185.3		4,185.3		4,163.7
Total Assets	4,872.0		4,872.0		4,635.6
Current liabilities	623.9		623.9		527.4
Non-current liabilities	1,319.8		1,319.8		1,349.2
Total Liabilities and Shareholders' Equity	4,872.0		4,872.0		4,635.6
Company's share of income (loss) from SSAT	7.4	$ 9.3	17.2	$ 23.2
Ocean Transportation
Financial information for equity method investment
Company's share of income (loss) from SSAT	7.4	9.3	17.2	23.2
SSAT
Investments in affiliates
Investment in SSAT	113.7		113.7		$ 96.2
Financial information for equity method investment
Operating revenue	299.9	329.5	876.7	948.7
Operating costs and expenses	(288.5)	(311.8)	(852.8)	(903.9)
Operating (loss) income	11.4	17.7	23.9	44.8
Net Income (Loss)	19.9	22.8	44.8	59.2
SSAT
Financial information for equity method investment
Company's share of income (loss) from SSAT	$ 7.4	$ 9.3	$ 17.2	$ 23.2

Amount of asset recognized for present right to economic benefit.

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