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Restructuring and Impairment - Additional Information (Details) - USD ($) $ in Millions	3 Months Ended		12 Months Ended
	Jun. 30, 2026	Jun. 30, 2025	Mar. 31, 2026	Mar. 31, 2025
Restructuring Cost and Reserve [Line Items]
Restructuring and impairment expenses, net	$ 19	$ 85
Accelerated depreciation		65
Richmond and Fairmont Plants
Restructuring Cost and Reserve [Line Items]
Restructuring costs	1	44
Changzhou Plant
Restructuring Cost and Reserve [Line Items]
Restructuring costs		20
2025 Efficiency Plan
Restructuring Cost and Reserve [Line Items]
Restructuring and impairment expenses, net	15	83	$ 163	$ 2
Accelerated depreciation			86
Employee-related expenses	12		60	$ 2
Professional fees	3		$ 21
Asia And South America
Restructuring Cost and Reserve [Line Items]
Professional fees	1
Europe \| 2025 Efficiency Plan
Restructuring Cost and Reserve [Line Items]
Professional fees	2
Restructuring costs	12
Income Statement Location [Axis]: us-gaap:SellingGeneralAndAdministrativeExpense \| Asia And South America
Restructuring Cost and Reserve [Line Items]
Restructuring costs	2	19
Employees
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Restructuring costs		20
Employees \| 2025 Efficiency Plan
Restructuring Cost and Reserve [Line Items]
Restructuring charges	12
Employees \| Europe \| 2025 Efficiency Plan
Restructuring Cost and Reserve [Line Items]
Restructuring costs	10
Employees \| Income Statement Location [Axis]: us-gaap:SellingGeneralAndAdministrativeExpense \| Asia And South America
Restructuring Cost and Reserve [Line Items]
Restructuring costs	$ 1	$ 18