Short-term Borrowings and Long-term Debt (Debt Repayments) (Details) - USD ($) $ in Millions	3 Months Ended
Apr. 30, 2023	Apr. 30, 2022
Debt Instrument [Line Items]
Repayment	$ 1,784	$ 926
2.55% Debt, Due 2023 \| Unsecured Debt
Debt Instrument [Line Items]
Principal Amount	$ 1,750
Fixed Interest Rate	2.55%
Repayment	$ 1,750

Face (par) amount of debt instrument at time of issuance.

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

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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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The cash outflow for debt initially having maturity due after one year or beyond the normal operating cycle, if longer.

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