The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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Balance Type:	credit
Period Type:	instant

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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- Definition

Amount of cash inflow from contractual arrangement with the lender, including but not limited to, letter of credit, standby letter of credit and revolving credit arrangements.

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Debt and Financing Activities - Revolving Credit Facilities (Details) - Revolving Credit Facility - USD ($)	12 Months Ended
	Mar. 31, 2025	Mar. 31, 2024	May 08, 2025	Nov. 07, 2022
Senior Unsecured Credit Facility (the 2022 Credit Facility) \| Unsecured debt
Line of Credit Facility [Line Items]
Credit facility borrowing capacity				$ 4,000,000,000.0
Senior Unsecured Credit Facility (the 2022 Credit Facility), Canadian Dollar, British Pound Sterling, and Euros Sublimit \| Unsecured debt
Line of Credit Facility [Line Items]
Credit facility borrowing capacity				$ 3,600,000,000
Amount borrowed under facility	$ 0	$ 0
Credit facility outstanding	$ 0	$ 0
Senior Unsecured Credit Facility (364 Day Credit Facility) \| Subsequent Event \| Unsecured debt
Line of Credit Facility [Line Items]
Credit facility borrowing capacity			$ 1,000,000,000.0