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Debt and Financing Activities - Long-Term Debt (Details) € in Millions, $ in Millions					12 Months Ended
	Dec. 03, 2025 USD ($)	Nov. 17, 2025 EUR (€)	May 30, 2025 USD ($)	Sep. 10, 2024 USD ($)	Mar. 31, 2026 USD ($)	Mar. 31, 2025 USD ($)	Mar. 31, 2024 USD ($)
Debt Instrument [Line Items]
Debt outstanding					$ 6,500	$ 5,700
Current portion of long-term debt					1,267	1,191
Retired and redeemed outstanding principal amount					$ 1,207	$ 519	$ 288
Loans payable
Debt Instrument [Line Items]
Redemption price (as percent)			101.00%	101.00%
Loans payable | Minimum
Debt Instrument [Line Items]
Debt instrument, redemption period (in days)			10 days	10 days
Loans payable | Maximum
Debt Instrument [Line Items]
Debt instrument, redemption period (in days)			60 days	60 days
4.65% Notes due May 30, 2030 | Loans payable
Debt Instrument [Line Items]
Interest rate on debt instruments (as percent)			4.65%		4.65%
Aggregate principal amount			$ 650
4.95% Notes due May 30, 2032 | Loans payable
Debt Instrument [Line Items]
Interest rate on debt instruments (as percent)			4.95%		4.95%
Aggregate principal amount			$ 650
5.25% Notes due May 30, 2035 | Loans payable
Debt Instrument [Line Items]
Interest rate on debt instruments (as percent)			5.25%		5.25%
Aggregate principal amount			$ 700
Notes | Loans payable
Debt Instrument [Line Items]
Proceeds from issuance, net			$ 2,000
4.25% Notes due September 15, 2029 | Loans payable
Debt Instrument [Line Items]
Interest rate on debt instruments (as percent)				4.25%	4.25%
Aggregate principal amount				$ 500
Proceeds from issuance, net				$ 496
5.25% Notes due February 15, 2026
Debt Instrument [Line Items]
Interest rate on debt instruments (as percent)				5.25%
5.25% Notes due February 15, 2026 | Loans payable
Debt Instrument [Line Items]
Retired and redeemed outstanding principal amount				$ 500
Redemption price (as percent)				100.00%
1.50% Notes Due November 17, 2025 | Loans payable
Debt Instrument [Line Items]
Interest rate on debt instruments (as percent)		1.50%
Retired and redeemed outstanding principal amount | €		€ 600
0.90% Notes due December 3, 2025 | Loans payable
Debt Instrument [Line Items]
Interest rate on debt instruments (as percent)	0.90%				0.90%
Retired and redeemed outstanding principal amount	$ 500

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