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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Percentage of principal amount of debt redeemed.

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

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Gross amount of debt extinguished.

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Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

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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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Borrowings - Long-Term Debt, Debt Issued (Details) - USD ($) $ in Millions	3 Months Ended
	Sep. 30, 2022	Mar. 31, 2022	Mar. 31, 2021
U.S dollar. fixed-rate notes
Notes Issued
Aggregate amount of debt issued	$ 3,250	$ 1,800
U.S dollar. fixed-rate notes \| Minimum
Notes Issued
Credit facility term	3 years	5 years
Coupon rate (as a percent)	4.00%	2.20%
U.S dollar. fixed-rate notes \| Maximum
Notes Issued
Credit facility term	30 years	30 years
Coupon rate (as a percent)	4.90%	3.43%
Euro fixed-rate notes
Notes Issued
Aggregate amount of debt issued		$ 2,300
Euro fixed-rate notes \| Minimum
Notes Issued
Credit facility term		8 years
Coupon rate (as a percent)		0.875%
Euro fixed-rate notes \| Maximum
Notes Issued
Credit facility term		12 years
Coupon rate (as a percent)		1.25%
IBM Credit LLC \| Fixed rate debt due in 2021 to 2023
Notes Issued
Outstanding debt redeemed			$ 1,750
Aggregate principal redeemed (as a percent)			100.00%
Loss upon redemption on notes			$ (22)