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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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Percentage price of original principal amount of debt at which debt can be redeemed by the issuer.

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Fair value amount of debt instrument that was repurchased.

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No definition available.

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Face (par) amount of the original debt instrument that was repurchased.

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No definition available.

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- Definition

Amount, after accumulated amortization, of debt premium.

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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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Amount of cash paid for interest, including, but not limited to, capitalized interest and payment to settle zero-coupon bond attributable to accreted interest of debt discount and debt instrument with insignificant coupon interest rate in relation to effective interest rate of borrowing attributable to accreted interest of debt discount; classified as operating and investing activities.

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Amount of long-term debt payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing after fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of long-term debt payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of long-term debt payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing in fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of long-term debt payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing in fourth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of long-term debt payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing in third fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of long-term debt payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing in second fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of cash outflow for cost from early extinguishment and prepayment of debt. Includes, but is not limited to, third-party cost, premium paid, and other fee paid to lender directly for debt extinguishment or debt prepayment. Excludes accrued interest.

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Debt and Financing Activities - Tender Offer and Other Information (Details) - USD ($) $ in Millions		12 Months Ended
	Jul. 23, 2021	Mar. 31, 2023	Mar. 31, 2022	Mar. 31, 2021	Dec. 15, 2022
Debt Instrument [Line Items]
Payments for debt extinguishments		$ 0	$ 184	$ 0
Loss on debt extinguishment		0	191	$ 0
Scheduled principal payments of long-term debt in 2024		968
Scheduled principal payments of long-term debt in 2025		39
Scheduled principal payments of long-term debt in 2026		1,700
Scheduled principal payments of long-term debt in 2027		1,200
Scheduled principal payments of long-term debt in 2028		376
Scheduled principal payments of long-term debt, thereafter		$ 1,300
Loans payable
Debt Instrument [Line Items]
Redemption price (percent)		101.00%
2.85% Notes due March 15, 2023 \| Loans payable
Debt Instrument [Line Items]
Interest rate on debt instruments (percent)	2.85%	2.85%			2.85%
3.80% Notes due March 15, 2024 \| Loans payable
Debt Instrument [Line Items]
Interest rate on debt instruments (percent)	3.80%	3.80%
7.65% Debentures due March 1, 2027 \| Loans payable
Debt Instrument [Line Items]
Interest rate on debt instruments (percent)	7.65%	7.65%
3.95% Notes due February 16, 2028 \| Loans payable
Debt Instrument [Line Items]
Interest rate on debt instruments (percent)	3.95%	3.95%
4.75% Notes due May 30, 2029 \| Loans payable
Debt Instrument [Line Items]
Interest rate on debt instruments (percent)	4.75%	4.75%
6.00% Notes due March 1, 2041 \| Loans payable
Debt Instrument [Line Items]
Interest rate on debt instruments (percent)	6.00%	6.00%
4.88% Notes due March 15, 2044 \| Loans payable
Debt Instrument [Line Items]
Interest rate on debt instruments (percent)	4.88%	4.88%
Tender Offer Notes \| Loans payable
Debt Instrument [Line Items]
Debt instrument, repurchase amount	$ 1,100
Debt Instrument, repurchased face amount	$ 922
Redemption price (percent)	100.00%
Payments for debt extinguishments	$ 182
Accrued and unpaid interest	$ 14
Loss on debt extinguishment			191
Debt premiums			182
Write-off of unamortized debt issuance costs and transaction fees			$ 9