Consolidated Statements of Operations - USD ($)	12 Months Ended
	Mar. 31, 2024	Mar. 31, 2023	Mar. 31, 2022
Income Statement [Abstract]
Net sales	$ 16,210,000,000	$ 18,486,000,000	$ 17,149,000,000
Cost of goods sold (exclusive of depreciation and amortization)	13,704,000,000	15,996,000,000	14,354,000,000
Selling, general and administrative expenses	717,000,000	679,000,000	631,000,000
Depreciation and amortization	554,000,000	540,000,000	550,000,000
Interest expense and amortization of debt issuance costs	298,000,000	274,000,000	227,000,000
Research and development expenses	98,000,000	95,000,000	92,000,000
Loss on extinguishment of debt, net	5,000,000	0	64,000,000
Restructuring and impairment, net	42,000,000	33,000,000	1,000,000
Equity in net income of non-consolidated affiliates	(4,000,000)	(16,000,000)	(8,000,000)
Other (income) expenses, net	(22,000,000)	79,000,000	(61,000,000)
Total expenses	15,392,000,000	17,680,000,000	15,850,000,000
Income from continuing operations before income tax provision	818,000,000	806,000,000	1,299,000,000
Income tax provision	218,000,000	147,000,000	281,000,000
Net income from continuing operations	600,000,000	659,000,000	1,018,000,000
Loss from discontinued operations, net of tax	0	(2,000,000)	(63,000,000)
Net income	600,000,000	657,000,000	955,000,000
Net income attributable to noncontrolling interests	0	(1,000,000)	1,000,000
Net income attributable to our common shareholder	$ 600,000,000	$ 658,000,000	$ 954,000,000
Weighted average common shares outstanding - basic (in shares)	1,100	1,100	1,100
Weighted average common shares outstanding - diluted (in shares)	1,100	1,100	1,100
Earnings per share - basic
From continuing operations attributable to our common shareholder, basic	$ 545,455	$ 600,000	$ 924,545
From discontinued operations attributable to our common shareholder, basic	0	(1,818)	(57,273)
Attributable to our common shareholder, basic	545,455	598,182	867,273
Earnings per share - diluted
From continuing operations attributable to our common shareholder, diluted	545,455	600,000	924,545
From discontinued operations attributable to our common shareholder, diluted	0	(1,818)	(57,273)
Attributable to our common shareholder, diluted	$ 545,455	$ 598,182	$ 867,273