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

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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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- Definition

The cash inflow from additional borrowings, net of cash paid to third parties in connection with debt origination.

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No definition available.

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- Definition

The cash inflow from a debt initially having maturity due after one year or beyond the operating cycle, if longer.

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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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Debt and Financing Activities - Long-Term Debt (Details)		12 Months Ended
	Feb. 17, 2017 USD ($)	Mar. 31, 2017 USD ($)	Mar. 31, 2016 USD ($)	Mar. 31, 2015 USD ($)	Feb. 17, 2017 EUR (€)	Feb. 17, 2017 GBP (£)
Debt Instrument [Line Items]
Total debt outstanding		$ 8,362,000,000	$ 8,107,000,000
Net proceeds from issuance of notes		1,824,000,000	0	$ 3,000,000
Repayments of long-term debt		$ 1,601,000,000	1,598,000,000	$ 353,000,000
Notes
Debt Instrument [Line Items]
Proceeds from Debt, Net of Issuance Costs	$ 1,800,000,000
Debt Instrument, Redemption Price, Percentage		101.00%
Repayments of long-term debt			93,000,000
Long-term Debt, Current Maturities
Debt Instrument [Line Items]
Total debt outstanding		$ 1,057,000,000	1,610,000,000
0.63% Euro Notes due August 17, 2021 \| Notes
Debt Instrument [Line Items]
Aggregate principal amount \| €					€ 600,000,000
Debt interest rate (percent)					0.63%	0.63%
4.00% Euro Bonds due October 18, 2016 \| Notes
Debt Instrument [Line Items]
Repayments of long-term debt		$ 385,000,000
5.70% Notes due March 1, 2017 \| Notes
Debt Instrument [Line Items]
Debt interest rate (percent)		5.70%
Repayments of long-term debt		$ 500,000,000
1.29% Notes Due March 10, 2017 \| Notes
Debt Instrument [Line Items]
Debt interest rate (percent)		1.29%
Repayments of long-term debt		$ 700,000,000
Floating Rate Notes \| Notes
Debt Instrument [Line Items]
Repayments of long-term debt			$ 400,000,000
0.95% Notes Due December 4 2015 \| Notes
Debt Instrument [Line Items]
Debt interest rate (percent)			0.95%
Repayments of long-term debt			$ 500,000,000
3.25% Notes Due March 1 2016 \| Notes
Debt Instrument [Line Items]
Debt interest rate (percent)			3.25%
Repayments of long-term debt			$ 600,000,000
1.50% Euro Notes due November 17, 2025 \| Notes
Debt Instrument [Line Items]
Aggregate principal amount \| €					€ 600,000,000
Debt interest rate (percent)					1.50%	1.50%
3.13% Sterling Notes due February 17, 2029 \| Notes
Debt Instrument [Line Items]
Aggregate principal amount \| £						£ 450,000,000
Debt interest rate (percent)					3.13%	3.13%