BORROWINGS - Components of long-term debt (Details) - USD ($) $ in Millions	Mar. 31, 2026	Mar. 31, 2025
BORROWINGS
Financing lease and other obligations	$ 204.0	$ 290.0
Total	3,104.0	3,190.0
Less: Unamortized discount	4.0	4.0
Less: Unamortized debt issuance costs	12.0	14.0
Less: Current portion of debt	796.0	129.0
Total long-term debt	$ 2,293.0	3,042.0
Finance lease and other obligations, interest rate (as a percent)	5.39%
Unsecured senior notes due 2034, including cross-currency swaps
BORROWINGS
Debt instrument, weighted-average interest rate (as a percent)	3.84%
Unsecured senior notes due 2026
BORROWINGS
Long-term debt	$ 700.0	700.0
Debt instrument, weighted-average interest rate (as a percent)	2.05%
Unsecured senior notes due 2028
BORROWINGS
Long-term debt	$ 500.0	500.0
Debt instrument, weighted-average interest rate (as a percent)	2.70%
Unsecured senior notes due 2031
BORROWINGS
Long-term debt	$ 650.0	650.0
Debt instrument, weighted-average interest rate (as a percent)	3.15%
Unsecured senior notes due 2034
BORROWINGS
Long-term debt	$ 500.0	500.0
Debt instrument, weighted-average interest rate (as a percent)	6.35%
Unsecured senior notes due 2041
BORROWINGS
Long-term debt	$ 550.0	$ 550.0
Debt instrument, weighted-average interest rate (as a percent)	4.10%

It represents the amount of debt excluding finance lease obligations.

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Amount, after accumulated amortization, of debt discount.

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