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

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

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Date when the debt instrument is scheduled to be fully repaid, in YYYY-MM-DD format.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Amount after unamortized (discount) premium and debt issuance costs of long-term debt classified as noncurrent and excluding amounts to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Debt (Details) € in Millions, £ in Millions, $ in Millions	3 Months Ended	6 Months Ended
Debt (Details) € in Millions, £ in Millions, $ in Millions	Jul. 31, 2021	Oct. 31, 2021 USD ($)	Oct. 31, 2021 EUR (€)	Oct. 31, 2021 GBP (£)	Apr. 30, 2021 USD ($)	Apr. 30, 2021 EUR (€)	Apr. 30, 2021 GBP (£)
Debt Instrument [Line Items]
Long-term debt, including current portion		$ 2,331			$ 2,354
Long-term debt		2,331			2,354
2.25% notes, due January 15, 2023 [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount		$ 250			$ 250
Debt Instrument, Maturity Date	Jan. 15, 2023	Jan. 15, 2023
Debt Instrument, Interest Rate, Stated Percentage		2.25%	2.25%	2.25%	2.25%	2.25%	2.25%
Long-term debt, including current portion		$ 250			$ 249
3.50% senior notes, due April 15, 2025 [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount		$ 300			$ 300
Debt Instrument, Maturity Date	Apr. 15, 2025	Apr. 15, 2025
Debt Instrument, Interest Rate, Stated Percentage		3.50%	3.50%	3.50%	3.50%	3.50%	3.50%
Long-term debt, including current portion		$ 298			$ 298
1.20% notes, due July 7, 2026 [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount \| €			€ 300			€ 300
Debt Instrument, Maturity Date	Jul. 07, 2026	Jul. 07, 2026
Debt Instrument, Interest Rate, Stated Percentage		1.20%	1.20%	1.20%	1.20%	1.20%	1.20%
Long-term debt, including current portion		$ 345			$ 362
2.60% notes, due July 7, 2028 [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount \| £				£ 300			£ 300
Debt Instrument, Maturity Date	Jul. 07, 2028	Jul. 07, 2028
Debt Instrument, Interest Rate, Stated Percentage		2.60%	2.60%	2.60%	2.60%	2.60%	2.60%
Long-term debt, including current portion		$ 407			$ 415
4.00% senior notes, due April 15, 2038 [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount		$ 300			$ 300
Debt Instrument, Maturity Date	Apr. 15, 2038	Apr. 15, 2038
Debt Instrument, Interest Rate, Stated Percentage		4.00%	4.00%	4.00%	4.00%	4.00%	4.00%
Long-term debt, including current portion		$ 295			$ 294
3.75% notes, due January 15, 2043 [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount		$ 250			$ 250
Debt Instrument, Maturity Date	Jan. 15, 2043	Jan. 15, 2043
Debt Instrument, Interest Rate, Stated Percentage		3.75%	3.75%	3.75%	3.75%	3.75%	3.75%
Long-term debt, including current portion		$ 248			$ 248
4.50% notes, due July 15, 2045 [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount		$ 500			$ 500
Debt Instrument, Maturity Date	Jul. 15, 2045	Jul. 15, 2045
Debt Instrument, Interest Rate, Stated Percentage		4.50%	4.50%	4.50%	4.50%	4.50%	4.50%
Long-term debt, including current portion		$ 488			$ 488