BORROWINGS - Components of long-term debt (Details) - USD ($) $ in Millions	Jun. 30, 2026	Mar. 31, 2026
BORROWINGS
Financing lease and other obligations	$ 185	$ 204
Total	3,085	3,104
Less: Unamortized discount	3	4
Less: Unamortized debt issuance costs	11	12
Less: Current portion of debt	781	796
Total long-term debt	$ 2,289	2,293
Finance lease and other obligations, interest rate (as a percent)	5.54%
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	700
Debt instrument, weighted-average interest rate (as a percent)	2.05%
Unsecured senior notes due 2028
BORROWINGS
Long-term debt	$ 500	500
Debt instrument, weighted-average interest rate (as a percent)	2.70%
Unsecured senior notes due 2031
BORROWINGS
Long-term debt	$ 650	650
Debt instrument, weighted-average interest rate (as a percent)	3.15%
Unsecured senior notes due 2034
BORROWINGS
Long-term debt	$ 500	500
Debt instrument, weighted-average interest rate (as a percent)	6.35%
Unsecured senior notes due 2041
BORROWINGS
Long-term debt	$ 550	$ 550
Debt instrument, weighted-average interest rate (as a percent)	4.10%

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