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Debt and Financing Activities - Long-Term Debt (Details)				12 Months Ended
	Aug. 12, 2021 USD ($)	Jul. 23, 2021 USD ($)	Dec. 03, 2020 USD ($)	Mar. 31, 2022 USD ($)	Mar. 31, 2021 USD ($)	Mar. 31, 2020 USD ($)	Mar. 31, 2020 EUR (€)	Jul. 17, 2021 USD ($)	Jul. 17, 2021 EUR (€)	Dec. 01, 2020 USD ($)	Nov. 30, 2020 USD ($)
Debt Instrument [Line Items]
Repayments of long-term debt				$ 1,648,000,000	$ 1,040,000,000	$ 298,000,000
Payments for debt extinguishments				184,000,000	0	0
Loss on debt extinguishment				191,000,000	0	$ 0
Scheduled principal payments of long-term debt in 2023				799,000,000
Scheduled principal payments of long-term debt in 2024				966,000,000
Scheduled principal payments of long-term debt in 2025				35,000,000
Scheduled principal payments of long-term debt in 2026				1,200,000,000
Scheduled principal payments of long-term debt in 2027				1,200,000,000
Scheduled principal payments of long-term debt, thereafter				1,700,000,000
Total debt				5,900,000,000	7,100,000,000
Less: Current portion				799,000,000	742,000,000
Total debt outstanding				$ 5,879,000,000	7,148,000,000
Notes Payable
Debt Instrument [Line Items]
Redemption price (percent)				101.00%
0.90% Notes due December 3, 2025 | Loans payable
Debt Instrument [Line Items]
Debt interest rate (percent)			0.90%	0.90%
Aggregate principal amount			$ 500,000,000
Proceeds from issuance, net			$ 496,000,000
Total debt outstanding				$ 500,000,000	500,000,000
1.30% Notes due August 15, 2026 | Loans payable
Debt Instrument [Line Items]
Debt interest rate (percent)	1.30%			1.30%
Aggregate principal amount	$ 500,000,000
Proceeds from issuance, net	$ 495,000,000
Total debt outstanding				$ 498,000,000	0
4.75% Notes Due March 1, 2021 | Loans payable
Debt Instrument [Line Items]
Debt interest rate (percent)										4.75%
Aggregate principal amount										$ 323,000,000
Notes Due November 30, 2020 | Loans payable
Debt Instrument [Line Items]
Debt interest rate (percent)											3.65%
Aggregate principal amount											$ 700,000,000
Floating Rate Euro Notes due February 12, 2020 | Loans payable
Debt Instrument [Line Items]
Repayments of long-term debt | €							€ 250,000,000
2.85% Notes due March 15, 2023 | Loans payable
Debt Instrument [Line Items]
Debt interest rate (percent)		2.85%		2.85%
Total debt outstanding				$ 360,000,000	400,000,000
3.80% Notes due March 15, 2024 | Loans payable
Debt Instrument [Line Items]
Debt interest rate (percent)		3.80%		3.80%
Total debt outstanding				$ 918,000,000	1,100,000,000
7.65% Debentures due March 1, 2027 | Loans payable
Debt Instrument [Line Items]
Debt interest rate (percent)		7.65%		7.65%
Total debt outstanding				$ 150,000,000	167,000,000
3.95% Notes due February 16, 2028 | Loans payable
Debt Instrument [Line Items]
Debt interest rate (percent)		3.95%		3.95%
Total debt outstanding				$ 343,000,000	600,000,000
4.75% Notes due May 30, 2029 | Loans payable
Debt Instrument [Line Items]
Debt interest rate (percent)		4.75%		4.75%
Total debt outstanding				$ 196,000,000	400,000,000
6.00% Notes due March 1, 2041 | Loans payable
Debt Instrument [Line Items]
Debt interest rate (percent)		6.00%		6.00%
Total debt outstanding				$ 217,000,000	282,000,000
4.88% Notes due March 15, 2044 | Loans payable
Debt Instrument [Line Items]
Debt interest rate (percent)		4.88%		4.88%
Total debt outstanding				$ 255,000,000	411,000,000
Tender Offer Notes | Loans payable
Debt Instrument [Line Items]
Redemption price (percent)		100.00%
Debt Instrument, repurchased face amount		$ 922,000,000
Debt instrument, repurchase amount		1,100,000,000
Payments for debt extinguishments		182,000,000
Accrued and unpaid interest		14,000,000
Loss on debt extinguishment		191,000,000		$ (191,000,000)
Write-off of Deferred Debt Issuance Cost and Transaction Costs		9,000,000
Debt premiums		$ 182,000,000
0.63% Euro Notes due August 17, 2021 | Loans payable
Debt Instrument [Line Items]
Debt interest rate (percent)				0.63%				0.63%	0.63%
Debt Instrument, repurchased face amount								$ 709,000,000	€ 600,000,000
Total debt outstanding				$ 0	$ 704,000,000

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