Debt - Commercial Paper Notes (Details) - USD ($)	Jun. 30, 2025	Mar. 31, 2025
Line of Credit Facility [Line Items]
Long-term debt	$ 5,488,000,000	$ 5,663,000,000
Commercial Paper
Line of Credit Facility [Line Items]
Maximum borrowing capacity	$ 2,750,000,000
Maturity from the date of issue	397 days
Long-term debt	$ 0	175,000,000.0
Line of credit \| Revolving Credit Facility
Line of Credit Facility [Line Items]
Maximum borrowing capacity		$ 2,250,000,000

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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- 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.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 235
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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.

+ References

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- Definition

Period between issuance and maturity of long-term debt, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

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